diff --git a/apps/backend/src/renovation/furniture-selection.ts b/apps/backend/src/renovation/furniture-selection.ts
new file mode 100644
index 0000000..8b0882c
--- /dev/null
+++ b/apps/backend/src/renovation/furniture-selection.ts
@@ -0,0 +1,52 @@
+import {
+  FurnitureOptionStatus,
+  FurnitureRequirementStatus,
+} from './entities/furniture.entities';
+
+export interface FurnitureSelectionState {
+  currentlySelected: boolean;
+  favorite: boolean;
+  status: FurnitureOptionStatus;
+}
+
+export function deselectFurnitureOption(
+  option: FurnitureSelectionState,
+): FurnitureSelectionState {
+  return {
+    ...option,
+    currentlySelected: false,
+    status:
+      option.status === FurnitureOptionStatus.Selected
+        ? option.favorite
+          ? FurnitureOptionStatus.Favorite
+          : FurnitureOptionStatus.Reviewing
+        : option.status,
+  };
+}
+
+export function toggleFurnitureSelection(
+  option: FurnitureSelectionState,
+  requirementStatus: FurnitureRequirementStatus,
+): {
+  option: FurnitureSelectionState;
+  requirementStatus: FurnitureRequirementStatus;
+} {
+  if (option.currentlySelected) {
+    return {
+      option: deselectFurnitureOption(option),
+      requirementStatus:
+        option.status === FurnitureOptionStatus.Selected
+          ? FurnitureRequirementStatus.DecisionOpen
+          : requirementStatus,
+    };
+  }
+
+  return {
+    option: {
+      ...option,
+      currentlySelected: true,
+      status: FurnitureOptionStatus.Selected,
+    },
+    requirementStatus: FurnitureRequirementStatus.Selected,
+  };
+}
diff --git a/apps/backend/src/renovation/furniture.service.ts b/apps/backend/src/renovation/furniture.service.ts
index 19a13dd..69eff1d 100644
--- a/apps/backend/src/renovation/furniture.service.ts
+++ b/apps/backend/src/renovation/furniture.service.ts
@@ -40,6 +40,10 @@ import {
   sumMoney,
 } from './furniture-pricing';
 import { FurnitureRepository } from './furniture.repository';
+import {
+  deselectFurnitureOption,
+  toggleFurnitureSelection,
+} from './furniture-selection';
 import { RenovationRepository } from './renovation.repository';
 
 @Injectable()
@@ -430,7 +434,7 @@ export class FurnitureService {
       const options = manager.getRepository(FurnitureOptionEntity);
       const candidate = await options.findOneBy({ id, projectId });
       if (!candidate || candidate.deletedAt) this.notFound();
-      await manager
+      const requirement = await manager
         .getRepository(FurnitureRequirementEntity)
         .createQueryBuilder('requirement')
         .setLock('pessimistic_write')
@@ -456,39 +460,47 @@ export class FurnitureService {
           'Die Alternative wurde zwischenzeitlich geändert. Laden Sie die Daten neu.',
         );
       if (
-        [
+        !option.currentlySelected &&
+        ([
           FurnitureOptionStatus.Archived,
           FurnitureOptionStatus.Unavailable,
           FurnitureOptionStatus.Rejected,
           FurnitureOptionStatus.Returned,
         ].includes(option.status) ||
-        [
-          FurnitureAvailability.Unavailable,
-          FurnitureAvailability.Discontinued,
-        ].includes(option.availability)
+          [
+            FurnitureAvailability.Unavailable,
+            FurnitureAvailability.Discontinued,
+          ].includes(option.availability))
       )
         this.conflict('Diese Alternative ist nicht auswählbar.');
-      await options.update(
-        {
-          projectId,
-          requirementId: option.requirementId,
-          currentlySelected: true,
-        },
-        { currentlySelected: false },
-      );
-      option.currentlySelected = true;
-      option.status = FurnitureOptionStatus.Selected;
+      if (!option.currentlySelected) {
+        const previousSelections = await options.find({
+          where: {
+            projectId,
+            requirementId: option.requirementId,
+            currentlySelected: true,
+          },
+        });
+        for (const previous of previousSelections) {
+          Object.assign(previous, deselectFurnitureOption(previous));
+        }
+        await options.save(previousSelections);
+      }
+      const transition = toggleFurnitureSelection(option, requirement.status);
+      Object.assign(option, transition.option);
       const saved = await options.save(option);
       await manager
         .getRepository(FurnitureRequirementEntity)
         .update(
           { id: option.requirementId, projectId },
-          { status: FurnitureRequirementStatus.Selected },
+          { status: transition.requirementStatus },
         );
       await this.activity(
         projectId,
         userId,
-        'furniture.option-selected',
+        saved.currentlySelected
+          ? 'furniture.option-selected'
+          : 'furniture.option-deselected',
         { optionId: id, requirementId: option.requirementId },
         manager,
       );
diff --git a/apps/backend/src/renovation/tests/furniture-selection.spec.ts b/apps/backend/src/renovation/tests/furniture-selection.spec.ts
new file mode 100644
index 0000000..3f8aac1
--- /dev/null
+++ b/apps/backend/src/renovation/tests/furniture-selection.spec.ts
@@ -0,0 +1,41 @@
+import { describe, expect, it } from 'vitest';
+import {
+  FurnitureOptionStatus,
+  FurnitureRequirementStatus,
+} from '../entities/furniture.entities';
+import { toggleFurnitureSelection } from '../furniture-selection';
+
+describe('furniture selection', () => {
+  it('removes a selected option from the cost selection', () => {
+    const result = toggleFurnitureSelection(
+      {
+        currentlySelected: true,
+        favorite: false,
+        status: FurnitureOptionStatus.Selected,
+      },
+      FurnitureRequirementStatus.Selected,
+    );
+
+    expect(result).toEqual({
+      option: {
+        currentlySelected: false,
+        favorite: false,
+        status: FurnitureOptionStatus.Reviewing,
+      },
+      requirementStatus: FurnitureRequirementStatus.DecisionOpen,
+    });
+  });
+
+  it('keeps the favorite marker when a selected favorite is deselected', () => {
+    const result = toggleFurnitureSelection(
+      {
+        currentlySelected: true,
+        favorite: true,
+        status: FurnitureOptionStatus.Selected,
+      },
+      FurnitureRequirementStatus.Selected,
+    );
+
+    expect(result.option.status).toBe(FurnitureOptionStatus.Favorite);
+  });
+});
diff --git a/apps/frontend/src/app/features/projects/furniture-grid.component.ts b/apps/frontend/src/app/features/projects/furniture-grid.component.ts
index 3ca0ec4..b43face 100644
--- a/apps/frontend/src/app/features/projects/furniture-grid.component.ts
+++ b/apps/frontend/src/app/features/projects/furniture-grid.component.ts
@@ -690,7 +690,7 @@ export class FurnitureGridComponent implements OnChanges {
       {
         field: 'currentlySelected',
         headerName: 'Auswahl',
-        valueFormatter: (p) => (p.value ? '◉ Ausgewählt' : '○ auswählen'),
+        valueFormatter: (p) => (p.value ? '◉ Auswahl aufheben' : '○ auswählen'),
         sortable: false,
       },
       {
diff --git a/apps/frontend/src/app/features/projects/furniture-planning.component.ts b/apps/frontend/src/app/features/projects/furniture-planning.component.ts
index aff26a7..720a6ff 100644
--- a/apps/frontend/src/app/features/projects/furniture-planning.component.ts
+++ b/apps/frontend/src/app/features/projects/furniture-planning.component.ts
@@ -420,10 +420,11 @@ const statusLabels: Record<string, string> = {
                         <button
                           type="button"
                           class="ui-button"
+                          [class.ui-button--secondary]="option.currentlySelected"
                           (click)="select(option)"
-                          [disabled]="option.currentlySelected"
+                          [attr.aria-pressed]="option.currentlySelected"
                         >
-                          Auswählen
+                          {{ option.currentlySelected ? 'Auswahl aufheben' : 'Auswählen' }}
                         </button>
                         <button
                           type="button"