diff --git a/frontend/src/app/components/apartment-form/apartment-form.css b/frontend/src/app/components/apartment-form/apartment-form.css
index 42d30cd..e42a8b5 100644
--- a/frontend/src/app/components/apartment-form/apartment-form.css
+++ b/frontend/src/app/components/apartment-form/apartment-form.css
@@ -27,17 +27,6 @@
   background: var(--surface);
   box-shadow: 0 1px 0 rgba(255, 255, 255, 0.04);
 }
-fieldset {
-  min-width: 0;
-  margin: 0;
-  padding: 0;
-  border: 0;
-}
-.primary-action mat-spinner {
-  display: inline-block;
-  margin-right: 8px;
-  vertical-align: middle;
-}
 .form-grid {
   display: grid;
   grid-template-columns: minmax(0, 1fr);
diff --git a/frontend/src/app/components/apartment-form/apartment-form.html b/frontend/src/app/components/apartment-form/apartment-form.html
index 13a8847..7eba1d4 100644
--- a/frontend/src/app/components/apartment-form/apartment-form.html
+++ b/frontend/src/app/components/apartment-form/apartment-form.html
@@ -26,7 +26,10 @@
     @if (error()) {
       <div class="alert-error" role="alert">{{ error() }}</div>
     }
-    <fieldset [disabled]="saving()" [attr.inert]="saving() ? '' : null">
+    <p class="visually-hidden" role="status" aria-live="polite">
+      {{ saving() ? 'Enregistrement en cours.' : '' }}
+    </p>
+    <fieldset class="busy-fieldset" [disabled]="saving()" [attr.inert]="saving() ? '' : null">
       <div class="form-grid">
         <mat-form-field appearance="outline"
           ><mat-label>Nom de l'appartement</mat-label
@@ -77,7 +80,7 @@
       <div class="form-actions">
         <button mat-button type="button" (click)="closed.emit()">Annuler</button
         ><button mat-flat-button type="submit" class="primary-action">
-          <span aria-live="polite">
+          <span>
             @if (saving()) {
               <mat-spinner diameter="18" aria-hidden="true" /> Enregistrement…
             } @else {
diff --git a/frontend/src/app/components/apartment-form/apartment-form.spec.ts b/frontend/src/app/components/apartment-form/apartment-form.spec.ts
index 1b23af3..74e0c75 100644
--- a/frontend/src/app/components/apartment-form/apartment-form.spec.ts
+++ b/frontend/src/app/components/apartment-form/apartment-form.spec.ts
@@ -58,6 +58,7 @@ describe('ApartmentForm', () => {
     fixture.detectChanges();
 
     expect(fixture.nativeElement.querySelector('fieldset').disabled).toBe(true);
+    expect(fixture.nativeElement.querySelector('[role=status]').closest('fieldset')).toBeNull();
     expect(fixture.nativeElement.textContent).toContain('Enregistrement…');
     expect(fixture.nativeElement.textContent).toContain(
       'Impossible d’enregistrer cet appartement.',
diff --git a/frontend/src/app/components/apartment-list/apartment-list.ts b/frontend/src/app/components/apartment-list/apartment-list.ts
index 965d6cf..a59ea7e 100644
--- a/frontend/src/app/components/apartment-list/apartment-list.ts
+++ b/frontend/src/app/components/apartment-list/apartment-list.ts
@@ -3,7 +3,7 @@ import { MatButtonModule } from '@angular/material/button';
 import { MatProgressBarModule } from '@angular/material/progress-bar';
 import { MatProgressSpinnerModule } from '@angular/material/progress-spinner';
 import { Apartment } from '../../services/apartment.service';
-import { LoadState } from '../../services/workspace.service';
+import { LoadState } from '../../services/workspace-resource';
 
 @Component({
   selector: 'app-apartment-list',
diff --git a/frontend/src/app/components/apartments-page/apartments-page.html b/frontend/src/app/components/apartments-page/apartments-page.html
index 413f86c..7a16dfc 100644
--- a/frontend/src/app/components/apartments-page/apartments-page.html
+++ b/frontend/src/app/components/apartments-page/apartments-page.html
@@ -13,8 +13,8 @@
   } @else {
     <app-apartment-form
       [apartment]="editingApartment()"
-      [saving]="workspace.apartmentSaving()"
-      [saveError]="workspace.apartmentSaveError()"
+      [saving]="workspace.apartmentSaving(editingApartment()?.id)"
+      [saveError]="workspace.apartmentSaveError(editingApartment()?.id)"
       (closed)="closeForm()"
       (saved)="saveApartment($event)"
     />
diff --git a/frontend/src/app/components/apartments-page/apartments-page.spec.ts b/frontend/src/app/components/apartments-page/apartments-page.spec.ts
index 21905a2..07ee526 100644
--- a/frontend/src/app/components/apartments-page/apartments-page.spec.ts
+++ b/frontend/src/app/components/apartments-page/apartments-page.spec.ts
@@ -9,8 +9,9 @@ describe('ApartmentsPage', () => {
   const workspace = {
     apartments: signal<Apartment[]>([]),
     apartmentLoadState: signal({ loaded: false, loading: true, error: '' }),
-    apartmentSaving: signal(false),
-    apartmentSaveError: signal(''),
+    apartmentSaving: vi.fn(() => false),
+    apartmentSaveError: vi.fn(() => ''),
+    clearApartmentSaveError: vi.fn(),
     deletingApartmentIds: signal<ReadonlySet<string>>(new Set()),
     apartmentDeleteErrors: signal<Record<string, string>>({}),
     loadApartments: () => undefined,
diff --git a/frontend/src/app/components/apartments-page/apartments-page.ts b/frontend/src/app/components/apartments-page/apartments-page.ts
index 6f1dba9..2a3f6ee 100644
--- a/frontend/src/app/components/apartments-page/apartments-page.ts
+++ b/frontend/src/app/components/apartments-page/apartments-page.ts
@@ -20,13 +20,13 @@ export class ApartmentsPage {
   }
 
   openAddForm(): void {
-    this.workspace.apartmentSaveError.set('');
+    this.workspace.clearApartmentSaveError();
     this.editingApartment.set(null);
     this.showForm.set(true);
   }
 
   openEditForm(apartment: Apartment): void {
-    this.workspace.apartmentSaveError.set('');
+    this.workspace.clearApartmentSaveError(apartment.id);
     this.editingApartment.set(apartment);
     this.showForm.set(true);
   }
diff --git a/frontend/src/app/components/lease-card/lease-card.spec.ts b/frontend/src/app/components/lease-card/lease-card.spec.ts
index 244091b..d0d5180 100644
--- a/frontend/src/app/components/lease-card/lease-card.spec.ts
+++ b/frontend/src/app/components/lease-card/lease-card.spec.ts
@@ -4,13 +4,30 @@ import { LeaseCard } from './lease-card';
 describe('LeaseCard', () => {
   it('resolves apartment, tenants, and every status label', () => {
     const fixture = TestBed.createComponent(LeaseCard);
-    fixture.componentRef.setInput('apartments', [{ id: 'apartment-1', name: 'T2', address: '', purchasePrice: 0, description: '' }]);
+    fixture.componentRef.setInput('apartments', [
+      { id: 'apartment-1', name: 'T2', address: '', purchasePrice: 0, description: '' },
+    ]);
     fixture.componentRef.setInput('tenants', [
-      { id: 'tenant-1', firstName: 'Camille', lastName: 'Martin', email: '', phone: '', address: '' },
+      {
+        id: 'tenant-1',
+        firstName: 'Camille',
+        lastName: 'Martin',
+        email: '',
+        phone: '',
+        address: '',
+      },
       { id: 'tenant-2', firstName: 'Alex', lastName: 'Durand', email: '', phone: '', address: '' },
     ]);
     fixture.componentRef.setInput('lease', {
-      apartmentId: 'apartment-1', tenantIds: ['tenant-1', 'missing', 'tenant-2'], guarantors: [], startDate: '', endDate: '', monthlyRent: 0, monthlyCharges: 0, securityDeposit: 0, status: 'DRAFT',
+      apartmentId: 'apartment-1',
+      tenantIds: ['tenant-1', 'missing', 'tenant-2'],
+      guarantors: [],
+      startDate: '',
+      endDate: '',
+      monthlyRent: 0,
+      monthlyCharges: 0,
+      securityDeposit: 0,
+      status: 'DRAFT',
     });
     const component = fixture.componentInstance;
 
@@ -19,8 +36,41 @@ describe('LeaseCard', () => {
     expect(component.statusLabel()).toBe('Bail en préparation');
     fixture.componentRef.setInput('lease', { ...component.lease(), status: 'ACTIVE' });
     expect(component.statusLabel()).toBe('Bail actif');
-    fixture.componentRef.setInput('lease', { ...component.lease(), apartmentId: 'missing', status: 'ARCHIVED' });
+    fixture.componentRef.setInput('lease', {
+      ...component.lease(),
+      apartmentId: 'missing',
+      status: 'ARCHIVED',
+    });
     expect(component.apartmentName()).toBe('Bien inconnu');
     expect(component.statusLabel()).toBe('Bail archivé');
   });
+
+  it('shows local Bail PDF download progress and failure', () => {
+    const fixture = TestBed.createComponent(LeaseCard);
+    fixture.componentRef.setInput('apartments', []);
+    fixture.componentRef.setInput('tenants', []);
+    fixture.componentRef.setInput('lease', {
+      id: 'lease-1',
+      apartmentId: 'apartment-1',
+      tenantIds: [],
+      guarantors: [],
+      startDate: '2026-01-01',
+      endDate: '2027-01-01',
+      monthlyRent: 800,
+      monthlyCharges: 50,
+      securityDeposit: 800,
+      status: 'ACTIVE',
+    });
+    fixture.componentRef.setInput('downloading', true);
+    fixture.detectChanges();
+
+    const download = fixture.nativeElement.querySelector('.card-actions button');
+    expect(download.disabled).toBe(true);
+    expect(download.textContent).toContain('Téléchargement…');
+
+    fixture.componentRef.setInput('downloading', false);
+    fixture.componentRef.setInput('downloadError', 'Impossible de télécharger ce bail.');
+    fixture.detectChanges();
+    expect(fixture.nativeElement.textContent).toContain('Impossible de télécharger ce bail.');
+  });
 });
diff --git a/frontend/src/app/components/lease-form/lease-form.css b/frontend/src/app/components/lease-form/lease-form.css
index 2677ff7..979af3c 100644
--- a/frontend/src/app/components/lease-form/lease-form.css
+++ b/frontend/src/app/components/lease-form/lease-form.css
@@ -28,17 +28,6 @@
   border-radius: 22px;
   background: var(--surface);
 }
-fieldset {
-  min-width: 0;
-  margin: 0;
-  padding: 0;
-  border: 0;
-}
-.primary-action mat-spinner {
-  display: inline-block;
-  margin-right: 8px;
-  vertical-align: middle;
-}
 .guarantor-section {
   margin-top: 18px;
 }
diff --git a/frontend/src/app/components/lease-form/lease-form.html b/frontend/src/app/components/lease-form/lease-form.html
index 7fab034..91d83fc 100644
--- a/frontend/src/app/components/lease-form/lease-form.html
+++ b/frontend/src/app/components/lease-form/lease-form.html
@@ -29,7 +29,10 @@
     @if (error()) {
       <div class="alert-error" role="alert">{{ error() }}</div>
     }
-    <fieldset [disabled]="saving()" [attr.inert]="saving() ? '' : null">
+    <p class="visually-hidden" role="status" aria-live="polite">
+      {{ saving() ? 'Enregistrement en cours.' : '' }}
+    </p>
+    <fieldset class="busy-fieldset" [disabled]="saving()" [attr.inert]="saving() ? '' : null">
       <section class="form-section">
         <div class="section-heading">
           <span>01</span>
@@ -143,7 +146,7 @@
       </section>
     </fieldset>
   </form>
-  <fieldset [disabled]="saving()" [attr.inert]="saving() ? '' : null">
+  <fieldset class="busy-fieldset" [disabled]="saving()" [attr.inert]="saving() ? '' : null">
     <section class="guarantor-section">
       <div class="section-heading">
         <span>03</span>
@@ -171,7 +174,7 @@
       class="primary-action"
       [disabled]="saving()"
     >
-      <span aria-live="polite">
+      <span>
         @if (saving()) {
           <mat-spinner diameter="18" aria-hidden="true" /> Enregistrement…
         } @else {
diff --git a/frontend/src/app/components/leases-page/leases-page.html b/frontend/src/app/components/leases-page/leases-page.html
index b88b06d..9760f05 100644
--- a/frontend/src/app/components/leases-page/leases-page.html
+++ b/frontend/src/app/components/leases-page/leases-page.html
@@ -60,8 +60,8 @@
                 [tenants]="workspace.tenants()"
                 [deleting]="!!lease.id && workspace.deletingLeaseIds().has(lease.id)"
                 [deleteError]="lease.id ? (workspace.leaseDeleteErrors()[lease.id] ?? '') : ''"
-                [downloading]="!!lease.id && workspace.downloadingLeaseIds().has(lease.id)"
-                [downloadError]="lease.id ? (workspace.leaseDownloadErrors()[lease.id] ?? '') : ''"
+                [downloading]="!!lease.id && workspace.leaseDownloading(lease.id)"
+                [downloadError]="lease.id ? workspace.leaseDownloadError(lease.id) : ''"
                 (pdfRequested)="workspace.downloadLeasePdf($event)"
                 (deleteRequested)="workspace.deleteLease($event)"
               />
diff --git a/frontend/src/app/components/leases-page/leases-page.spec.ts b/frontend/src/app/components/leases-page/leases-page.spec.ts
index fb246ec..14524b4 100644
--- a/frontend/src/app/components/leases-page/leases-page.spec.ts
+++ b/frontend/src/app/components/leases-page/leases-page.spec.ts
@@ -17,8 +17,11 @@ describe('LeasesPage', () => {
     saveLease: vi.fn(),
     deleteLease: vi.fn(),
     downloadLeasePdf: vi.fn(),
-    leaseSaving: signal(false),
-    leaseSaveError: signal(''),
+    leaseSaving: vi.fn(() => false),
+    leaseSaveError: vi.fn(() => ''),
+    clearLeaseSaveError: vi.fn(),
+    leaseDownloading: vi.fn(() => false),
+    leaseDownloadError: vi.fn(() => ''),
   };
 
   beforeEach(() => {
diff --git a/frontend/src/app/components/leases-page/leases-page.ts b/frontend/src/app/components/leases-page/leases-page.ts
index 6277db2..77cd4a6 100644
--- a/frontend/src/app/components/leases-page/leases-page.ts
+++ b/frontend/src/app/components/leases-page/leases-page.ts
@@ -41,7 +41,7 @@ export class LeasesPage {
   }
 
   openForm(): void {
-    this.workspace.leaseSaveError.set('');
+    this.workspace.clearLeaseSaveError();
     this.showForm.set(true);
   }
   closeForm(): void {
diff --git a/frontend/src/app/components/tenant-card/tenant-card.spec.ts b/frontend/src/app/components/tenant-card/tenant-card.spec.ts
index 237dbef..5bf2503 100644
--- a/frontend/src/app/components/tenant-card/tenant-card.spec.ts
+++ b/frontend/src/app/components/tenant-card/tenant-card.spec.ts
@@ -41,6 +41,23 @@ describe('TenantCard', () => {
     expect(fixture.nativeElement.textContent).toContain('Envoi : 50 %');
   });
 
+  it('falls back to indeterminate upload feedback when no total is available', () => {
+    const fixture = TestBed.createComponent(TenantCard);
+    fixture.componentRef.setInput('tenant', {
+      id: 'tenant-1',
+      firstName: 'Camille',
+      lastName: 'Martin',
+      email: 'camille@example.com',
+      phone: '',
+      address: '',
+    });
+    fixture.componentRef.setInput('uploading', true);
+    fixture.detectChanges();
+
+    expect(fixture.nativeElement.textContent).toContain('Envoi…');
+    expect(fixture.nativeElement.querySelector('mat-progress-bar')).not.toBeNull();
+  });
+
   it('shows progress only on the selected attachment download', () => {
     const fixture = TestBed.createComponent(TenantCard);
     fixture.componentRef.setInput('tenant', {
diff --git a/frontend/src/app/components/tenant-form/tenant-form.css b/frontend/src/app/components/tenant-form/tenant-form.css
index 6c178d7..79b97dc 100644
--- a/frontend/src/app/components/tenant-form/tenant-form.css
+++ b/frontend/src/app/components/tenant-form/tenant-form.css
@@ -26,12 +26,6 @@
   border-radius: 22px;
   background: var(--surface);
 }
-fieldset {
-  min-width: 0;
-  margin: 0;
-  padding: 0;
-  border: 0;
-}
 .alert-error {
   margin-bottom: 18px;
   padding: 13px 15px;
@@ -40,11 +34,6 @@ fieldset {
   background: var(--danger-soft);
   color: var(--danger);
 }
-.primary-action mat-spinner {
-  display: inline-block;
-  margin-right: 8px;
-  vertical-align: middle;
-}
 .form-grid {
   display: grid;
   gap: 2px;
diff --git a/frontend/src/app/components/tenant-form/tenant-form.html b/frontend/src/app/components/tenant-form/tenant-form.html
index 14ff2c7..85101ec 100644
--- a/frontend/src/app/components/tenant-form/tenant-form.html
+++ b/frontend/src/app/components/tenant-form/tenant-form.html
@@ -25,7 +25,10 @@
     @if (saveError()) {
       <div class="alert-error" role="alert">{{ saveError() }}</div>
     }
-    <fieldset [disabled]="saving()" [attr.inert]="saving() ? '' : null">
+    <p class="visually-hidden" role="status" aria-live="polite">
+      {{ saving() ? 'Enregistrement en cours.' : '' }}
+    </p>
+    <fieldset class="busy-fieldset" [disabled]="saving()" [attr.inert]="saving() ? '' : null">
       <div class="form-grid">
         <mat-form-field appearance="outline"
           ><mat-label>Prénom</mat-label
@@ -79,7 +82,7 @@
       <div class="form-actions">
         <button mat-button type="button" (click)="cancelled.emit()">Annuler</button
         ><button mat-flat-button type="submit" class="primary-action">
-          <span aria-live="polite">
+          <span>
             @if (saving()) {
               <mat-spinner diameter="18" aria-hidden="true" /> Enregistrement…
             } @else {
diff --git a/frontend/src/app/components/tenants-page/tenants-page.html b/frontend/src/app/components/tenants-page/tenants-page.html
index a68c196..fe6edea 100644
--- a/frontend/src/app/components/tenants-page/tenants-page.html
+++ b/frontend/src/app/components/tenants-page/tenants-page.html
@@ -57,7 +57,7 @@
                 [attachmentError]="
                   tenant.id ? (workspace.tenantAttachmentErrors()[tenant.id] ?? '') : ''
                 "
-                [uploading]="workspace.uploadingTenantIds().has(tenant.id!)"
+                [uploading]="tenant.id ? workspace.uploadingTenantIds().has(tenant.id) : false"
                 [uploadProgress]="
                   tenant.id ? (workspace.tenantUploadProgress()[tenant.id] ?? null) : null
                 "
@@ -83,8 +83,8 @@
 } @else {
   <app-tenant-form
     [tenant]="editingTenant()"
-    [saving]="workspace.tenantSaving()"
-    [saveError]="workspace.tenantSaveError()"
+    [saving]="workspace.tenantSaving(editingTenant()?.id)"
+    [saveError]="workspace.tenantSaveError(editingTenant()?.id)"
     (cancelled)="closeForm()"
     (submitted)="saveTenant($event)"
   />
diff --git a/frontend/src/app/components/tenants-page/tenants-page.spec.ts b/frontend/src/app/components/tenants-page/tenants-page.spec.ts
index 455483d..5e95bfc 100644
--- a/frontend/src/app/components/tenants-page/tenants-page.spec.ts
+++ b/frontend/src/app/components/tenants-page/tenants-page.spec.ts
@@ -1,4 +1,3 @@
-import { signal } from '@angular/core';
 import { TestBed } from '@angular/core/testing';
 import { TenantsPage } from './tenants-page';
 import { WorkspaceService } from '../../services/workspace.service';
@@ -9,7 +8,7 @@ describe('TenantsPage', () => {
       providers: [
         {
           provide: WorkspaceService,
-          useValue: { loadTenants: () => undefined, tenantSaveError: signal('') },
+          useValue: { loadTenants: () => undefined, clearTenantSaveError: () => undefined },
         },
       ],
     }),
diff --git a/frontend/src/app/components/tenants-page/tenants-page.ts b/frontend/src/app/components/tenants-page/tenants-page.ts
index e5dab15..7f197e9 100644
--- a/frontend/src/app/components/tenants-page/tenants-page.ts
+++ b/frontend/src/app/components/tenants-page/tenants-page.ts
@@ -23,12 +23,12 @@ export class TenantsPage {
   }
 
   openAddForm(): void {
-    this.workspace.tenantSaveError.set('');
+    this.workspace.clearTenantSaveError();
     this.editingTenant.set(null);
     this.showForm.set(true);
   }
   openEditForm(tenant: Tenant): void {
-    this.workspace.tenantSaveError.set('');
+    this.workspace.clearTenantSaveError(tenant.id);
     this.editingTenant.set(tenant);
     this.showForm.set(true);
   }
diff --git a/frontend/src/app/services/file-download.service.ts b/frontend/src/app/services/file-download.service.ts
new file mode 100644
index 0000000..e0254eb
--- /dev/null
+++ b/frontend/src/app/services/file-download.service.ts
@@ -0,0 +1,49 @@
+import { Injectable, signal } from '@angular/core';
+import { finalize, Observable } from 'rxjs';
+
+@Injectable({ providedIn: 'root' })
+export class FileDownloadService {
+  readonly pendingKeys = signal<ReadonlySet<string>>(new Set());
+  readonly errors = signal<Record<string, string>>({});
+
+  isPending(key: string): boolean {
+    return this.pendingKeys().has(key);
+  }
+
+  error(key: string): string {
+    return this.errors()[key] ?? '';
+  }
+
+  download(key: string, request: Observable<Blob>, fileName: string, errorMessage: string): void {
+    if (this.pendingKeys().has(key)) return;
+    this.pendingKeys.update((keys) => new Set(keys).add(key));
+    this.errors.update((errors) => this.withoutKey(errors, key));
+    request
+      .pipe(finalize(() => this.pendingKeys.update((keys) => this.without(keys, key))))
+      .subscribe({
+        next: (blob) => this.save(blob, fileName),
+        error: () => this.errors.update((errors) => ({ ...errors, [key]: errorMessage })),
+      });
+  }
+
+  private save(blob: Blob, fileName: string): void {
+    const url = URL.createObjectURL(blob);
+    const link = document.createElement('a');
+    link.href = url;
+    link.download = fileName;
+    link.click();
+    URL.revokeObjectURL(url);
+  }
+
+  private without(values: ReadonlySet<string>, value: string): ReadonlySet<string> {
+    const next = new Set(values);
+    next.delete(value);
+    return next;
+  }
+
+  private withoutKey<T>(record: Record<string, T>, key: string): Record<string, T> {
+    const next = { ...record };
+    delete next[key];
+    return next;
+  }
+}
diff --git a/frontend/src/app/services/session.service.ts b/frontend/src/app/services/session.service.ts
index 9a5af8e..f309a65 100644
--- a/frontend/src/app/services/session.service.ts
+++ b/frontend/src/app/services/session.service.ts
@@ -1,5 +1,5 @@
 import { HttpClient } from '@angular/common/http';
-import { Injectable, inject, signal } from '@angular/core';
+import { computed, Injectable, inject, signal } from '@angular/core';
 
 interface UserResponse {
   authenticated: boolean;
@@ -13,7 +13,7 @@ export type SessionStatus = 'checking' | 'authenticated' | 'anonymous' | 'error'
 export class SessionService {
   private readonly http = inject(HttpClient);
   readonly status = signal<SessionStatus>('checking');
-  readonly isLoggedIn = signal(false);
+  readonly isLoggedIn = computed(() => this.status() === 'authenticated');
   readonly username = signal('');
   readonly email = signal('');
 
@@ -21,13 +21,11 @@ export class SessionService {
     this.status.set('checking');
     this.http.get<UserResponse>('/api/user').subscribe({
       next: (user) => {
-        this.isLoggedIn.set(user.authenticated);
         this.status.set(user.authenticated ? 'authenticated' : 'anonymous');
         this.username.set(user.authenticated ? user.username || 'User' : '');
         this.email.set(user.authenticated ? user.email || '' : '');
       },
       error: () => {
-        this.isLoggedIn.set(false);
         this.status.set('error');
         this.username.set('');
         this.email.set('');
diff --git a/frontend/src/app/services/tenant-attachment-transfer.service.ts b/frontend/src/app/services/tenant-attachment-transfer.service.ts
new file mode 100644
index 0000000..f0e3e94
--- /dev/null
+++ b/frontend/src/app/services/tenant-attachment-transfer.service.ts
@@ -0,0 +1,104 @@
+import { HttpEventType } from '@angular/common/http';
+import { computed, Injectable, inject, signal } from '@angular/core';
+import { finalize } from 'rxjs';
+import { FileDownloadService } from './file-download.service';
+import { TenantAttachment, TenantService } from './tenant.service';
+
+@Injectable({ providedIn: 'root' })
+export class TenantAttachmentTransferService {
+  private readonly tenantService = inject(TenantService);
+  private readonly downloads = inject(FileDownloadService);
+  readonly errors = signal<Record<string, string>>({});
+  readonly uploadingTenantIds = signal<ReadonlySet<string>>(new Set());
+  readonly uploadProgress = signal<Record<string, number | null>>({});
+  readonly downloadingIds = computed<ReadonlySet<string>>(() => {
+    const prefix = 'attachment:';
+    return new Set(
+      [...this.downloads.pendingKeys()]
+        .filter((key) => key.startsWith(prefix))
+        .map((key) => key.slice(prefix.length)),
+    );
+  });
+  readonly downloadErrors = computed<Record<string, string>>(() => {
+    const prefix = 'attachment:';
+    return Object.fromEntries(
+      Object.entries(this.downloads.errors())
+        .filter(([key]) => key.startsWith(prefix))
+        .map(([key, error]) => [key.slice(prefix.length), error]),
+    );
+  });
+
+  upload(tenantId: string, file: File, onUploaded: (attachment: TenantAttachment) => void): void {
+    if (this.uploadingTenantIds().has(tenantId)) return;
+    this.errors.update((errors) => this.withoutKey(errors, tenantId));
+    this.uploadingTenantIds.update((ids) => new Set(ids).add(tenantId));
+    this.uploadProgress.update((progress) => ({ ...progress, [tenantId]: null }));
+    this.tenantService
+      .uploadAttachment(tenantId, file)
+      .pipe(
+        finalize(() => {
+          this.uploadingTenantIds.update((ids) => this.without(ids, tenantId));
+          this.uploadProgress.update((progress) => this.withoutKey(progress, tenantId));
+        }),
+      )
+      .subscribe({
+        next: (event) => {
+          if (event.type === HttpEventType.UploadProgress) {
+            const percent = event.total ? Math.round((event.loaded / event.total) * 100) : null;
+            this.uploadProgress.update((progress) => ({ ...progress, [tenantId]: percent }));
+          } else if (event.type === HttpEventType.Response && event.body) {
+            onUploaded(event.body);
+          }
+        },
+        error: (error: unknown) => {
+          const message = this.errorMessage(error, 'Impossible d’envoyer cette pièce jointe.');
+          this.errors.update((errors) => ({ ...errors, [tenantId]: message }));
+        },
+      });
+  }
+
+  download(tenantId: string, attachment: { id: string; fileName: string }): void {
+    this.downloads.download(
+      this.downloadKey(attachment.id),
+      this.tenantService.downloadAttachment(tenantId, attachment.id),
+      attachment.fileName,
+      'Impossible de télécharger cette pièce jointe.',
+    );
+  }
+
+  downloading(attachmentId: string): boolean {
+    return this.downloads.isPending(this.downloadKey(attachmentId));
+  }
+
+  downloadError(attachmentId: string): string {
+    return this.downloads.error(this.downloadKey(attachmentId));
+  }
+
+  private downloadKey(attachmentId: string): string {
+    return `attachment:${attachmentId}`;
+  }
+
+  private without(values: ReadonlySet<string>, value: string): ReadonlySet<string> {
+    const next = new Set(values);
+    next.delete(value);
+    return next;
+  }
+
+  private withoutKey<T>(record: Record<string, T>, key: string): Record<string, T> {
+    const next = { ...record };
+    delete next[key];
+    return next;
+  }
+
+  private errorMessage(error: unknown, fallback: string): string {
+    return typeof error === 'object' &&
+      error !== null &&
+      'error' in error &&
+      typeof error.error === 'object' &&
+      error.error !== null &&
+      'message' in error.error &&
+      typeof error.error.message === 'string'
+      ? error.error.message
+      : fallback;
+  }
+}
diff --git a/frontend/src/app/services/workspace-resource.ts b/frontend/src/app/services/workspace-resource.ts
new file mode 100644
index 0000000..a55cb27
--- /dev/null
+++ b/frontend/src/app/services/workspace-resource.ts
@@ -0,0 +1,114 @@
+import { signal } from '@angular/core';
+import { finalize, Observable } from 'rxjs';
+
+export interface LoadState {
+  loaded: boolean;
+  loading: boolean;
+  error: string;
+}
+
+interface ResourceMessages {
+  load: string;
+  save: string;
+  delete: string;
+}
+
+export class WorkspaceResource<T extends { id?: string }> {
+  readonly items = signal<T[]>([]);
+  readonly loadState = signal<LoadState>({ loaded: false, loading: false, error: '' });
+  readonly savingKeys = signal<ReadonlySet<string>>(new Set());
+  readonly saveErrors = signal<Record<string, string>>({});
+  readonly deletingIds = signal<ReadonlySet<string>>(new Set());
+  readonly deleteErrors = signal<Record<string, string>>({});
+  private revision = 0;
+
+  constructor(
+    private readonly loadRequest: () => Observable<T[]>,
+    private readonly messages: ResourceMessages,
+  ) {}
+
+  load(): void {
+    if (this.loadState().loading) return;
+    const revision = this.revision;
+    this.loadState.update((state) => ({ ...state, loading: true, error: '' }));
+    this.loadRequest().subscribe({
+      next: (items) => {
+        if (revision === this.revision) this.items.set(items);
+        this.loadState.set({ loaded: true, loading: false, error: '' });
+        if (revision !== this.revision) this.load();
+      },
+      error: () =>
+        this.loadState.update((state) => ({
+          ...state,
+          loading: false,
+          error: this.messages.load,
+        })),
+    });
+  }
+
+  save(key: string, request: Observable<T>, onSuccess?: () => void): void {
+    if (this.savingKeys().has(key)) return;
+    this.savingKeys.update((keys) => new Set(keys).add(key));
+    this.saveErrors.update((errors) => this.withoutKey(errors, key));
+    request
+      .pipe(finalize(() => this.savingKeys.update((keys) => this.without(keys, key))))
+      .subscribe({
+        next: (saved) => {
+          this.upsert(saved);
+          onSuccess?.();
+          this.load();
+        },
+        error: () => this.saveErrors.update((errors) => ({ ...errors, [key]: this.messages.save })),
+      });
+  }
+
+  delete(id: string, request: Observable<void>): void {
+    if (this.deletingIds().has(id)) return;
+    this.deletingIds.update((ids) => new Set(ids).add(id));
+    this.deleteErrors.update((errors) => this.withoutKey(errors, id));
+    request
+      .pipe(finalize(() => this.deletingIds.update((ids) => this.without(ids, id))))
+      .subscribe({
+        next: () => {
+          this.confirmChange((items) => items.filter((item) => item.id !== id));
+          this.load();
+        },
+        error: () =>
+          this.deleteErrors.update((errors) => ({ ...errors, [id]: this.messages.delete })),
+      });
+  }
+
+  upsert(saved: T): void {
+    this.confirmChange((items) =>
+      saved.id && items.some((item) => item.id === saved.id)
+        ? items.map((item) => (item.id === saved.id ? saved : item))
+        : [...items, saved],
+    );
+  }
+
+  update(id: string, updateItem: (item: T) => T): void {
+    this.confirmChange((items) => items.map((item) => (item.id === id ? updateItem(item) : item)));
+  }
+
+  clearSaveError(key: string): void {
+    this.saveErrors.update((errors) => this.withoutKey(errors, key));
+  }
+
+  private confirmChange(updateItems: (items: T[]) => T[]): void {
+    this.revision += 1;
+    this.items.update(updateItems);
+    this.loadState.update((state) => ({ ...state, loaded: true, error: '' }));
+  }
+
+  private without(values: ReadonlySet<string>, value: string): ReadonlySet<string> {
+    const next = new Set(values);
+    next.delete(value);
+    return next;
+  }
+
+  private withoutKey<V>(record: Record<string, V>, key: string): Record<string, V> {
+    const next = { ...record };
+    delete next[key];
+    return next;
+  }
+}
diff --git a/frontend/src/app/services/workspace.service.spec.ts b/frontend/src/app/services/workspace.service.spec.ts
index 3221b72..f753c66 100644
--- a/frontend/src/app/services/workspace.service.spec.ts
+++ b/frontend/src/app/services/workspace.service.spec.ts
@@ -107,6 +107,14 @@ describe('WorkspaceService', () => {
     service.loadApartments();
     expect(service.apartments()).toEqual([apartment]);
     expect(service.apartmentLoadState()).toEqual({ loaded: true, loading: true, error: '' });
+
+    refreshResponse.error(new Error('offline'));
+    expect(service.apartments()).toEqual([apartment]);
+    expect(service.apartmentLoadState()).toEqual({
+      loaded: true,
+      loading: false,
+      error: 'Impossible de charger les appartements.',
+    });
   });
 
   it('keeps a confirmed apartment save visible while reconciliation is pending', () => {
@@ -120,13 +128,13 @@ describe('WorkspaceService', () => {
     const saved = vi.fn();
 
     service.saveApartment(updatedApartment, apartment.id, saved);
-    expect(service.apartmentSaving()).toBe(true);
+    expect(service.apartmentSaving(apartment.id)).toBe(true);
 
     saveResponse.next(updatedApartment);
     saveResponse.complete();
     expect(saved).toHaveBeenCalled();
     expect(service.apartments()).toEqual([updatedApartment]);
-    expect(service.apartmentSaving()).toBe(false);
+    expect(service.apartmentSaving(apartment.id)).toBe(false);
     expect(service.apartmentLoadState().loading).toBe(true);
   });
 
@@ -144,6 +152,7 @@ describe('WorkspaceService', () => {
     service.loadApartments();
     service.saveApartment(updatedApartment, apartment.id);
     expect(service.apartments()).toEqual([updatedApartment]);
+    expect(service.apartmentLoadState().loaded).toBe(true);
 
     staleRefresh.next([apartment]);
     staleRefresh.complete();
@@ -151,6 +160,28 @@ describe('WorkspaceService', () => {
     expect(apartments.getApartments).toHaveBeenCalledTimes(2);
   });
 
+  it('scopes concurrent apartment saves and failures to their records', () => {
+    const firstSave = new Subject<typeof apartment>();
+    const secondApartment = { ...apartment, id: 'apartment-2', name: 'T3' };
+    const secondSave = new Subject<typeof secondApartment>();
+    apartments.updateApartment.mockReturnValueOnce(firstSave).mockReturnValueOnce(secondSave);
+    const service = TestBed.inject(WorkspaceService);
+    const firstConfirmed = vi.fn();
+
+    service.saveApartment(apartment, apartment.id, firstConfirmed);
+    service.saveApartment(secondApartment, secondApartment.id);
+    expect(service.apartmentSaving(apartment.id)).toBe(true);
+    expect(service.apartmentSaving(secondApartment.id)).toBe(true);
+
+    firstSave.error(new Error('offline'));
+    expect(firstConfirmed).not.toHaveBeenCalled();
+    expect(service.apartmentSaving(apartment.id)).toBe(false);
+    expect(service.apartmentSaveError(apartment.id)).toBe(
+      'Impossible d’enregistrer cet appartement.',
+    );
+    expect(service.apartmentSaving(secondApartment.id)).toBe(true);
+  });
+
   it('removes a confirmed deletion locally before reconciliation finishes', () => {
     const deleteResponse = new Subject<void>();
     const refreshResponse = new Subject<(typeof apartment)[]>();
@@ -170,6 +201,20 @@ describe('WorkspaceService', () => {
     expect(service.apartmentLoadState().loading).toBe(true);
   });
 
+  it('preserves a record and exposes a local error when deletion fails', () => {
+    apartments.deleteApartment.mockReturnValueOnce(throwError(() => new Error('offline')));
+    const service = TestBed.inject(WorkspaceService);
+    service.apartments.set([apartment]);
+
+    service.deleteApartment(apartment.id);
+
+    expect(service.apartments()).toEqual([apartment]);
+    expect(service.deletingApartmentIds().has(apartment.id)).toBe(false);
+    expect(service.apartmentDeleteErrors()[apartment.id]).toBe(
+      'Impossible de supprimer cet appartement.',
+    );
+  });
+
   it('reports attachment upload progress and keeps the confirmed attachment', () => {
     const attachment = { id: 'attachment-1', fileName: 'id.pdf' };
     const uploadEvents = new Subject<HttpEvent<typeof attachment>>();
@@ -180,6 +225,8 @@ describe('WorkspaceService', () => {
     service.tenants.set([tenant]);
 
     service.uploadTenantAttachment(tenant.id, new File(['id'], 'id.pdf'));
+    service.uploadTenantAttachment(tenant.id, new File(['duplicate'], 'duplicate.pdf'));
+    expect(tenants.uploadAttachment).toHaveBeenCalledTimes(1);
     expect(service.uploadingTenantIds().has(tenant.id)).toBe(true);
     expect(service.tenantUploadProgress()[tenant.id]).toBeNull();
 
diff --git a/frontend/src/app/services/workspace.service.ts b/frontend/src/app/services/workspace.service.ts
index ef6036d..96c9363 100644
--- a/frontend/src/app/services/workspace.service.ts
+++ b/frontend/src/app/services/workspace.service.ts
@@ -1,332 +1,192 @@
-import { Injectable, inject, signal } from '@angular/core';
-import { HttpEventType } from '@angular/common/http';
-import { finalize } from 'rxjs';
+import { Injectable, inject } from '@angular/core';
 import { Apartment, ApartmentService } from './apartment.service';
+import { FileDownloadService } from './file-download.service';
 import { Lease, LeaseService } from './lease.service';
 import { Tenant, TenantService } from './tenant.service';
+import { TenantAttachmentTransferService } from './tenant-attachment-transfer.service';
+import { WorkspaceResource } from './workspace-resource';
 
-export interface LoadState {
-  loaded: boolean;
-  loading: boolean;
-  error: string;
-}
-
-const initialLoadState: LoadState = { loaded: false, loading: false, error: '' };
+const newResourceKey = 'new';
 
 @Injectable({ providedIn: 'root' })
 export class WorkspaceService {
   private readonly apartmentService = inject(ApartmentService);
   private readonly tenantService = inject(TenantService);
   private readonly leaseService = inject(LeaseService);
-  private apartmentRevision = 0;
-  private tenantRevision = 0;
-  private leaseRevision = 0;
-  readonly apartments = signal<Apartment[]>([]);
-  readonly apartmentLoadState = signal<LoadState>(initialLoadState);
-  readonly apartmentSaving = signal(false);
-  readonly apartmentSaveError = signal('');
-  readonly deletingApartmentIds = signal<ReadonlySet<string>>(new Set());
-  readonly apartmentDeleteErrors = signal<Record<string, string>>({});
-  readonly tenants = signal<Tenant[]>([]);
-  readonly tenantLoadState = signal<LoadState>(initialLoadState);
-  readonly tenantSaving = signal(false);
-  readonly tenantSaveError = signal('');
-  readonly deletingTenantIds = signal<ReadonlySet<string>>(new Set());
-  readonly tenantDeleteErrors = signal<Record<string, string>>({});
-  readonly leases = signal<Lease[]>([]);
-  readonly leaseLoadState = signal<LoadState>(initialLoadState);
-  readonly leaseSaving = signal(false);
-  readonly leaseSaveError = signal('');
-  readonly deletingLeaseIds = signal<ReadonlySet<string>>(new Set());
-  readonly leaseDeleteErrors = signal<Record<string, string>>({});
-  readonly tenantAttachmentErrors = signal<Record<string, string>>({});
-  readonly uploadingTenantIds = signal<ReadonlySet<string>>(new Set());
-  readonly tenantUploadProgress = signal<Record<string, number | null>>({});
-  readonly downloadingAttachmentIds = signal<ReadonlySet<string>>(new Set());
-  readonly attachmentDownloadErrors = signal<Record<string, string>>({});
-  readonly downloadingLeaseIds = signal<ReadonlySet<string>>(new Set());
-  readonly leaseDownloadErrors = signal<Record<string, string>>({});
+  private readonly downloads = inject(FileDownloadService);
+  private readonly attachmentTransfers = inject(TenantAttachmentTransferService);
+
+  private readonly apartmentResource = new WorkspaceResource(
+    () => this.apartmentService.getApartments(),
+    {
+      load: 'Impossible de charger les appartements.',
+      save: 'Impossible d’enregistrer cet appartement.',
+      delete: 'Impossible de supprimer cet appartement.',
+    },
+  );
+  private readonly tenantResource = new WorkspaceResource(() => this.tenantService.getTenants(), {
+    load: 'Impossible de charger les locataires.',
+    save: 'Impossible d’enregistrer ce locataire.',
+    delete: 'Impossible de supprimer ce locataire.',
+  });
+  private readonly leaseResource = new WorkspaceResource(() => this.leaseService.getLeases(), {
+    load: 'Impossible de charger les baux.',
+    save: 'Impossible d’enregistrer ce bail.',
+    delete: 'Impossible de supprimer ce bail.',
+  });
+
+  readonly apartments = this.apartmentResource.items;
+  readonly apartmentLoadState = this.apartmentResource.loadState;
+  readonly deletingApartmentIds = this.apartmentResource.deletingIds;
+  readonly apartmentDeleteErrors = this.apartmentResource.deleteErrors;
+  readonly tenants = this.tenantResource.items;
+  readonly tenantLoadState = this.tenantResource.loadState;
+  readonly deletingTenantIds = this.tenantResource.deletingIds;
+  readonly tenantDeleteErrors = this.tenantResource.deleteErrors;
+  readonly leases = this.leaseResource.items;
+  readonly leaseLoadState = this.leaseResource.loadState;
+  readonly deletingLeaseIds = this.leaseResource.deletingIds;
+  readonly leaseDeleteErrors = this.leaseResource.deleteErrors;
+
+  readonly tenantAttachmentErrors = this.attachmentTransfers.errors;
+  readonly uploadingTenantIds = this.attachmentTransfers.uploadingTenantIds;
+  readonly tenantUploadProgress = this.attachmentTransfers.uploadProgress;
+  readonly downloadingAttachmentIds = this.attachmentTransfers.downloadingIds;
+  readonly attachmentDownloadErrors = this.attachmentTransfers.downloadErrors;
 
   loadApartments(): void {
-    if (this.apartmentLoadState().loading) return;
-    const revision = this.apartmentRevision;
-    this.apartmentLoadState.update((state) => ({ ...state, loading: true, error: '' }));
-    this.apartmentService.getApartments().subscribe({
-      next: (data) => {
-        if (revision === this.apartmentRevision) this.apartments.set(data);
-        this.apartmentLoadState.set({ loaded: true, loading: false, error: '' });
-        if (revision !== this.apartmentRevision) this.loadApartments();
-      },
-      error: () =>
-        this.apartmentLoadState.update((state) => ({
-          ...state,
-          loading: false,
-          error: 'Impossible de charger les appartements.',
-        })),
-    });
+    this.apartmentResource.load();
   }
+
   saveApartment(apartment: Apartment, id?: string, onSuccess?: () => void): void {
-    if (this.apartmentSaving()) return;
-    this.apartmentSaving.set(true);
-    this.apartmentSaveError.set('');
-    (id
-      ? this.apartmentService.updateApartment(id, apartment)
-      : this.apartmentService.createApartment(apartment)
-    )
-      .pipe(finalize(() => this.apartmentSaving.set(false)))
-      .subscribe({
-        next: (savedApartment) => {
-          this.apartmentRevision += 1;
-          this.apartments.update((items) => this.mergeById(items, savedApartment));
-          onSuccess?.();
-          this.loadApartments();
-        },
-        error: () => this.apartmentSaveError.set('Impossible d’enregistrer cet appartement.'),
-      });
+    this.apartmentResource.save(
+      this.resourceKey(id),
+      id
+        ? this.apartmentService.updateApartment(id, apartment)
+        : this.apartmentService.createApartment(apartment),
+      onSuccess,
+    );
   }
+
+  apartmentSaving(id?: string): boolean {
+    return this.apartmentResource.savingKeys().has(this.resourceKey(id));
+  }
+
+  apartmentSaveError(id?: string): string {
+    return this.apartmentResource.saveErrors()[this.resourceKey(id)] ?? '';
+  }
+
+  clearApartmentSaveError(id?: string): void {
+    this.apartmentResource.clearSaveError(this.resourceKey(id));
+  }
+
   deleteApartment(id: string): void {
-    if (
-      this.deletingApartmentIds().has(id) ||
-      !confirm('Êtes-vous sûr de vouloir supprimer cet appartement ?')
-    )
-      return;
-    this.deletingApartmentIds.update((ids) => new Set(ids).add(id));
-    this.apartmentDeleteErrors.update((errors) => this.withoutKey(errors, id));
-    this.apartmentService
-      .deleteApartment(id)
-      .pipe(finalize(() => this.deletingApartmentIds.update((ids) => this.without(ids, id))))
-      .subscribe({
-        next: () => {
-          this.apartmentRevision += 1;
-          this.apartments.update((items) => items.filter((item) => item.id !== id));
-          this.loadApartments();
-        },
-        error: () =>
-          this.apartmentDeleteErrors.update((errors) => ({
-            ...errors,
-            [id]: 'Impossible de supprimer cet appartement.',
-          })),
-      });
+    if (confirm('Êtes-vous sûr de vouloir supprimer cet appartement ?'))
+      this.apartmentResource.delete(id, this.apartmentService.deleteApartment(id));
   }
+
   loadTenants(): void {
-    if (this.tenantLoadState().loading) return;
-    const revision = this.tenantRevision;
-    this.tenantLoadState.update((state) => ({ ...state, loading: true, error: '' }));
-    this.tenantService.getTenants().subscribe({
-      next: (data) => {
-        if (revision === this.tenantRevision) this.tenants.set(data);
-        this.tenantLoadState.set({ loaded: true, loading: false, error: '' });
-        if (revision !== this.tenantRevision) this.loadTenants();
-      },
-      error: () =>
-        this.tenantLoadState.update((state) => ({
-          ...state,
-          loading: false,
-          error: 'Impossible de charger les locataires.',
-        })),
-    });
+    this.tenantResource.load();
   }
+
   saveTenant(tenant: Tenant, id?: string, onSuccess?: () => void): void {
-    if (this.tenantSaving()) return;
-    this.tenantSaving.set(true);
-    this.tenantSaveError.set('');
-    (id ? this.tenantService.updateTenant(id, tenant) : this.tenantService.createTenant(tenant))
-      .pipe(finalize(() => this.tenantSaving.set(false)))
-      .subscribe({
-        next: (savedTenant) => {
-          this.tenantRevision += 1;
-          this.tenants.update((items) => this.mergeById(items, savedTenant));
-          onSuccess?.();
-          this.loadTenants();
-        },
-        error: () => this.tenantSaveError.set('Impossible d’enregistrer ce locataire.'),
-      });
+    this.tenantResource.save(
+      this.resourceKey(id),
+      id ? this.tenantService.updateTenant(id, tenant) : this.tenantService.createTenant(tenant),
+      onSuccess,
+    );
   }
+
+  tenantSaving(id?: string): boolean {
+    return this.tenantResource.savingKeys().has(this.resourceKey(id));
+  }
+
+  tenantSaveError(id?: string): string {
+    return this.tenantResource.saveErrors()[this.resourceKey(id)] ?? '';
+  }
+
+  clearTenantSaveError(id?: string): void {
+    this.tenantResource.clearSaveError(this.resourceKey(id));
+  }
+
   deleteTenant(id: string): void {
-    if (
-      this.deletingTenantIds().has(id) ||
-      !confirm('Êtes-vous sûr de vouloir supprimer ce locataire ?')
-    )
-      return;
-    this.deletingTenantIds.update((ids) => new Set(ids).add(id));
-    this.tenantDeleteErrors.update((errors) => this.withoutKey(errors, id));
-    this.tenantService
-      .deleteTenant(id)
-      .pipe(finalize(() => this.deletingTenantIds.update((ids) => this.without(ids, id))))
-      .subscribe({
-        next: () => {
-          this.tenantRevision += 1;
-          this.tenants.update((items) => items.filter((item) => item.id !== id));
-          this.loadTenants();
-        },
-        error: () =>
-          this.tenantDeleteErrors.update((errors) => ({
-            ...errors,
-            [id]: 'Impossible de supprimer ce locataire.',
-          })),
-      });
+    if (confirm('Êtes-vous sûr de vouloir supprimer ce locataire ?'))
+      this.tenantResource.delete(id, this.tenantService.deleteTenant(id));
   }
+
   uploadTenantAttachment(tenantId: string, file: File): void {
-    if (this.uploadingTenantIds().has(tenantId)) return;
-    this.tenantAttachmentErrors.update((errors) => this.withoutKey(errors, tenantId));
-    this.uploadingTenantIds.update((ids) => new Set(ids).add(tenantId));
-    this.tenantUploadProgress.update((progress) => ({ ...progress, [tenantId]: null }));
-    this.tenantService
-      .uploadAttachment(tenantId, file)
-      .pipe(
-        finalize(() => {
-          this.uploadingTenantIds.update((ids) => this.without(ids, tenantId));
-          this.tenantUploadProgress.update((progress) => this.withoutKey(progress, tenantId));
-        }),
-      )
-      .subscribe({
-        next: (event) => {
-          if (event.type === HttpEventType.UploadProgress) {
-            const percent = event.total ? Math.round((event.loaded / event.total) * 100) : null;
-            this.tenantUploadProgress.update((progress) => ({ ...progress, [tenantId]: percent }));
-          } else if (event.type === HttpEventType.Response && event.body) {
-            this.tenantRevision += 1;
-            this.tenants.update((items) =>
-              items.map((item) =>
-                item.id === tenantId
-                  ? { ...item, attachments: this.mergeById(item.attachments ?? [], event.body!) }
-                  : item,
-              ),
-            );
-            this.loadTenants();
-          }
-        },
-        error: (error: unknown) => {
-          const message = this.errorMessage(error, 'Impossible d’envoyer cette pièce jointe.');
-          this.tenantAttachmentErrors.update((errors) => ({ ...errors, [tenantId]: message }));
-        },
-      });
-  }
-  downloadTenantAttachment(tenantId: string, attachment: { id: string; fileName: string }): void {
-    if (this.downloadingAttachmentIds().has(attachment.id)) return;
-    this.downloadingAttachmentIds.update((ids) => new Set(ids).add(attachment.id));
-    this.attachmentDownloadErrors.update((errors) => this.withoutKey(errors, attachment.id));
-    this.tenantService
-      .downloadAttachment(tenantId, attachment.id)
-      .pipe(
-        finalize(() =>
-          this.downloadingAttachmentIds.update((ids) => this.without(ids, attachment.id)),
-        ),
-      )
-      .subscribe({
-        next: (blob) => this.saveBlob(blob, attachment.fileName),
-        error: () =>
-          this.attachmentDownloadErrors.update((errors) => ({
-            ...errors,
-            [attachment.id]: 'Impossible de télécharger cette pièce jointe.',
-          })),
-      });
-  }
-  loadLeases(): void {
-    if (this.leaseLoadState().loading) return;
-    const revision = this.leaseRevision;
-    this.leaseLoadState.update((state) => ({ ...state, loading: true, error: '' }));
-    this.leaseService.getLeases().subscribe({
-      next: (data) => {
-        if (revision === this.leaseRevision) this.leases.set(data);
-        this.leaseLoadState.set({ loaded: true, loading: false, error: '' });
-        if (revision !== this.leaseRevision) this.loadLeases();
-      },
-      error: () =>
-        this.leaseLoadState.update((state) => ({
-          ...state,
-          loading: false,
-          error: 'Impossible de charger les baux.',
-        })),
+    this.attachmentTransfers.upload(tenantId, file, (attachment) => {
+      this.tenantResource.update(tenantId, (tenant) => ({
+        ...tenant,
+        attachments: [
+          ...(tenant.attachments ?? []).filter((item) => item.id !== attachment.id),
+          attachment,
+        ],
+      }));
+      this.tenantResource.load();
     });
   }
+
+  downloadTenantAttachment(tenantId: string, attachment: { id: string; fileName: string }): void {
+    this.attachmentTransfers.download(tenantId, attachment);
+  }
+
+  attachmentDownloading(attachmentId: string): boolean {
+    return this.attachmentTransfers.downloading(attachmentId);
+  }
+
+  attachmentDownloadError(attachmentId: string): string {
+    return this.attachmentTransfers.downloadError(attachmentId);
+  }
+
+  loadLeases(): void {
+    this.leaseResource.load();
+  }
+
   saveLease(lease: Lease, onSuccess?: () => void): void {
-    if (this.leaseSaving()) return;
-    this.leaseSaving.set(true);
-    this.leaseSaveError.set('');
-    this.leaseService
-      .createLease(lease)
-      .pipe(finalize(() => this.leaseSaving.set(false)))
-      .subscribe({
-        next: (savedLease) => {
-          this.leaseRevision += 1;
-          this.leases.update((items) => this.mergeById(items, savedLease));
-          onSuccess?.();
-          this.loadLeases();
-        },
-        error: () => this.leaseSaveError.set('Impossible d’enregistrer ce bail.'),
-      });
+    this.leaseResource.save(newResourceKey, this.leaseService.createLease(lease), onSuccess);
   }
+
+  leaseSaving(): boolean {
+    return this.leaseResource.savingKeys().has(newResourceKey);
+  }
+
+  leaseSaveError(): string {
+    return this.leaseResource.saveErrors()[newResourceKey] ?? '';
+  }
+
+  clearLeaseSaveError(): void {
+    this.leaseResource.clearSaveError(newResourceKey);
+  }
+
   deleteLease(id: string): void {
-    if (this.deletingLeaseIds().has(id) || !confirm('Êtes-vous sûr de vouloir supprimer ce bail ?'))
-      return;
-    this.deletingLeaseIds.update((ids) => new Set(ids).add(id));
-    this.leaseDeleteErrors.update((errors) => this.withoutKey(errors, id));
-    this.leaseService
-      .deleteLease(id)
-      .pipe(finalize(() => this.deletingLeaseIds.update((ids) => this.without(ids, id))))
-      .subscribe({
-        next: () => {
-          this.leaseRevision += 1;
-          this.leases.update((items) => items.filter((item) => item.id !== id));
-          this.loadLeases();
-        },
-        error: () =>
-          this.leaseDeleteErrors.update((errors) => ({
-            ...errors,
-            [id]: 'Impossible de supprimer ce bail.',
-          })),
-      });
+    if (confirm('Êtes-vous sûr de vouloir supprimer ce bail ?'))
+      this.leaseResource.delete(id, this.leaseService.deleteLease(id));
   }
+
   downloadLeasePdf(lease: Lease): void {
-    if (!lease.id || this.downloadingLeaseIds().has(lease.id)) return;
-    const id = lease.id;
-    this.downloadingLeaseIds.update((ids) => new Set(ids).add(id));
-    this.leaseDownloadErrors.update((errors) => this.withoutKey(errors, id));
-    this.leaseService
-      .downloadPdf(id)
-      .pipe(finalize(() => this.downloadingLeaseIds.update((ids) => this.without(ids, id))))
-      .subscribe({
-        next: (blob) => this.saveBlob(blob, `bail-${id}.pdf`),
-        error: () =>
-          this.leaseDownloadErrors.update((errors) => ({
-            ...errors,
-            [id]: 'Impossible de télécharger ce bail.',
-          })),
-      });
+    if (!lease.id) return;
+    this.downloads.download(
+      this.leaseDownloadKey(lease.id),
+      this.leaseService.downloadPdf(lease.id),
+      `bail-${lease.id}.pdf`,
+      'Impossible de télécharger ce bail.',
+    );
   }
-  private saveBlob(blob: Blob, fileName: string): void {
-    const url = URL.createObjectURL(blob);
-    const link = document.createElement('a');
-    link.href = url;
-    link.download = fileName;
-    link.click();
-    URL.revokeObjectURL(url);
+
+  leaseDownloading(leaseId: string): boolean {
+    return this.downloads.isPending(this.leaseDownloadKey(leaseId));
   }
-  private mergeById<T extends { id?: string }>(items: T[], saved: T): T[] {
-    return saved.id && items.some((item) => item.id === saved.id)
-      ? items.map((item) => (item.id === saved.id ? saved : item))
-      : [...items, saved];
+
+  leaseDownloadError(leaseId: string): string {
+    return this.downloads.error(this.leaseDownloadKey(leaseId));
   }
-  private without(ids: ReadonlySet<string>, id: string): ReadonlySet<string> {
-    const next = new Set(ids);
-    next.delete(id);
-    return next;
+
+  private resourceKey(id?: string): string {
+    return id ?? newResourceKey;
   }
-  private withoutKey<T>(record: Record<string, T>, key: string): Record<string, T> {
-    const next = { ...record };
-    delete next[key];
-    return next;
-  }
-  private errorMessage(error: unknown, fallback: string): string {
-    return typeof error === 'object' &&
-      error !== null &&
-      'error' in error &&
-      typeof error.error === 'object' &&
-      error.error !== null &&
-      'message' in error.error &&
-      typeof error.error.message === 'string'
-      ? error.error.message
-      : fallback;
+
+  private leaseDownloadKey(leaseId: string): string {
+    return `lease:${leaseId}`;
   }
 }
diff --git a/frontend/src/styles.scss b/frontend/src/styles.scss
index 4fb65a7..5bc3148 100644
--- a/frontend/src/styles.scss
+++ b/frontend/src/styles.scss
@@ -144,6 +144,30 @@ p {
   min-height: 220px;
 }
 
+.visually-hidden {
+  position: absolute;
+  width: 1px;
+  height: 1px;
+  padding: 0;
+  overflow: hidden;
+  clip: rect(0, 0, 0, 0);
+  white-space: nowrap;
+  border: 0;
+}
+
+.busy-fieldset {
+  min-width: 0;
+  margin: 0;
+  padding: 0;
+  border: 0;
+}
+
+.primary-action mat-spinner {
+  display: inline-block;
+  margin-right: 8px;
+  vertical-align: middle;
+}
+
 .load-error,
 .refresh-error {
   padding: 20px;