diff --git a/apps/backend/src/renovation/furniture-pricing.ts b/apps/backend/src/renovation/furniture-pricing.ts
index 8d2b6c8..c85cf23 100644
--- a/apps/backend/src/renovation/furniture-pricing.ts
+++ b/apps/backend/src/renovation/furniture-pricing.ts
@@ -36,3 +36,9 @@ export function sumMoney(values: readonly (string | number)[]): string {
   const total = values.reduce<number>((sum, value) => sum + cents(value), 0);
   return `${Math.floor(total / 100)}.${String(total % 100).padStart(2, '0')}`;
 }
+
+export function formatOptionalMoney(
+  value: number | null | undefined,
+): string | null {
+  return value == null ? null : value.toFixed(2);
+}
diff --git a/apps/backend/src/renovation/furniture.service.ts b/apps/backend/src/renovation/furniture.service.ts
index 07f20cd..19a13dd 100644
--- a/apps/backend/src/renovation/furniture.service.ts
+++ b/apps/backend/src/renovation/furniture.service.ts
@@ -34,7 +34,11 @@ import {
   FurnitureScenarioStatus,
   FurnitureScenarioType,
 } from './entities/furniture.entities';
-import { calculateFurnitureTotal, sumMoney } from './furniture-pricing';
+import {
+  calculateFurnitureTotal,
+  formatOptionalMoney,
+  sumMoney,
+} from './furniture-pricing';
 import { FurnitureRepository } from './furniture.repository';
 import { RenovationRepository } from './renovation.repository';
 
@@ -1317,8 +1321,8 @@ export class FurnitureService {
         'Dieser Datensatz wurde zwischenzeitlich geändert. Laden Sie die aktuellen Daten neu.',
       );
   }
-  private decimal(value?: number) {
-    return value === undefined ? null : value.toFixed(2);
+  private decimal(value?: number | null) {
+    return formatOptionalMoney(value);
   }
   private validation(message: string): never {
     throw new ApiError(ErrorCode.ValidationFailed, message, 400);
diff --git a/apps/backend/src/renovation/tests/furniture-pricing.spec.ts b/apps/backend/src/renovation/tests/furniture-pricing.spec.ts
index d43cb18..b150c90 100644
--- a/apps/backend/src/renovation/tests/furniture-pricing.spec.ts
+++ b/apps/backend/src/renovation/tests/furniture-pricing.spec.ts
@@ -1,5 +1,9 @@
 import { describe, expect, it } from 'vitest';
-import { calculateFurnitureTotal, sumMoney } from '../furniture-pricing';
+import {
+  calculateFurnitureTotal,
+  formatOptionalMoney,
+  sumMoney,
+} from '../furniture-pricing';
 
 describe('furniture price calculation', () => {
   it('includes quantity, shipping and additional costs and subtracts discounts cent-exactly', () => {
@@ -40,4 +44,10 @@ describe('furniture price calculation', () => {
   it('sums decimal money without binary floating point drift', () => {
     expect(sumMoney(['0.10', '0.20', '1299.99'])).toBe('1300.29');
   });
+
+  it('formats optional scenario price overrides without crashing for missing values', () => {
+    expect(formatOptionalMoney(undefined)).toBeNull();
+    expect(formatOptionalMoney(null)).toBeNull();
+    expect(formatOptionalMoney(12.5)).toBe('12.50');
+  });
 });
diff --git a/apps/frontend/src/app/shared/ui/toast/toast-host.component.ts b/apps/frontend/src/app/shared/ui/toast/toast-host.component.ts
index 4f17f17..79aac74 100644
--- a/apps/frontend/src/app/shared/ui/toast/toast-host.component.ts
+++ b/apps/frontend/src/app/shared/ui/toast/toast-host.component.ts
@@ -1,11 +1,18 @@
-import { Component, inject } from '@angular/core';
+import { Component, effect, inject, viewChild } from '@angular/core';
+import type { ElementRef } from '@angular/core';
 import { ToastService } from './toast.service';
 
 @Component({
   selector: 'ui-toast-host',
   standalone: true,
   template: `
-    <section class="ui-toast-region" aria-live="polite" aria-label="Meldungen">
+    <section
+      #region
+      class="ui-toast-region"
+      popover="manual"
+      aria-live="polite"
+      aria-label="Meldungen"
+    >
       @for (toast of toasts.messages(); track toast.id) {
         <article class="ui-toast" [class]="toast.tone">
           <div>
@@ -37,6 +44,11 @@ import { ToastService } from './toast.service';
         bottom: var(--space-4);
         z-index: var(--z-toast);
         width: min(26rem, calc(100vw - var(--space-7)));
+        margin: 0;
+        padding: 0;
+        border: 0;
+        background: transparent;
+        overflow: visible;
         display: grid;
         gap: var(--space-3);
       }
@@ -76,4 +88,24 @@ import { ToastService } from './toast.service';
 })
 export class UiToastHostComponent {
   readonly toasts = inject(ToastService);
+  private readonly region = viewChild<ElementRef<HTMLElement>>('region');
+
+  constructor() {
+    effect(() => {
+      const region = this.region()?.nativeElement;
+      const hasMessages = this.toasts.messages().length > 0;
+      if (!region || typeof region.showPopover !== 'function') return;
+
+      const isOpen = region.matches(':popover-open');
+      if (!hasMessages) {
+        if (isOpen) region.hidePopover();
+        return;
+      }
+
+      // Erneutes Oeffnen setzt den Toast im Top Layer auch vor einen bereits
+      // geoeffneten modalen Dialog.
+      if (isOpen) region.hidePopover();
+      region.showPopover();
+    });
+  }
 }
diff --git a/apps/frontend/src/app/shared/ui/ui-components.spec.ts b/apps/frontend/src/app/shared/ui/ui-components.spec.ts
index 9862167..d9da1ae 100644
--- a/apps/frontend/src/app/shared/ui/ui-components.spec.ts
+++ b/apps/frontend/src/app/shared/ui/ui-components.spec.ts
@@ -115,6 +115,15 @@ describe('shared UI components', () => {
     expect((fixture.nativeElement as HTMLElement).textContent).not.toContain('Gespeichert');
   });
 
+  it('places the toast region in the browser top layer', async () => {
+    await TestBed.configureTestingModule({ imports: [UiTestHostComponent] }).compileComponents();
+    const fixture = TestBed.createComponent(UiTestHostComponent);
+    fixture.detectChanges();
+
+    const region = (fixture.nativeElement as HTMLElement).querySelector('.ui-toast-region');
+    expect(region?.getAttribute('popover')).toBe('manual');
+  });
+
   it('emits empty state and pagination actions', async () => {
     await TestBed.configureTestingModule({ imports: [UiTestHostComponent] }).compileComponents();
     const fixture = TestBed.createComponent(UiTestHostComponent);