Pretty close to done, but had to pseudo code

db.json

@@ -4,25 +4,25 @@
       "id": 1,
       "name": "Sprite",
       "cost": 0.5,
-      "remaining": 10
+      "remaining": 6
     },
     {
       "id": 2,
       "name": "Coke",
       "cost": 0.5,
-      "remaining": 10
+      "remaining": 7
     },
     {
       "id": 3,
       "name": "Dr. Pepper",
       "cost": 0.75,
-      "remaining": 10
+      "remaining": -19
     },
     {
       "id": 4,
       "name": "Mr Pibbs",
       "cost": 0.5,
-      "remaining": 10
+      "remaining": 7
     }
   ]
 }

src/app/app.component.html

@@ -2,3 +2,4 @@ <h1>
   {{title}}
 </h1>
 <app-insert-coin></app-insert-coin>
+<app-select-item></app-select-item>

src/app/app.component.ts

@@ -1,5 +1,6 @@
 import { Component } from '@angular/core';
 
+
 @Component({
   selector: 'app-root',
   templateUrl: './app.component.html',

src/app/app.module.ts

@@ -8,11 +8,13 @@ import { InsertCoinComponent } from './insert-coin/insert-coin.component';
 
 import { ItemService } from './item/item.service';
 import { BalanceService } from './balance/balance.service';
+import { SelectItemComponent } from './select-item/select-item.component';
 
 @NgModule({
   declarations: [
     AppComponent,
-    InsertCoinComponent
+    InsertCoinComponent,
+    SelectItemComponent
   ],
   imports: [
     BrowserModule,

src/app/insert-coin/insert-coin.component.html

@@ -2,3 +2,4 @@
 <button class="button -yellow" (click)='addBalance(.05)'>05c</button>
 <button class="button -blue" (click)='addBalance(.10)'>10c</button>
 <button class="button -green" (click)='addBalance(.25)'>25c</button>
+<button class="button" (click)='returnCoins()'>Return Coins</button>

src/app/insert-coin/insert-coin.component.ts

@@ -21,4 +21,9 @@ export class InsertCoinComponent implements OnInit {
   	this.balanceService.addBalance(amount);
   }
 
+  returnCoins() {
+    this.balanceService.setBalance(0);
+    alert('Coins returned!');
+  }
+
 }

src/app/item/item.service.ts

@@ -3,6 +3,7 @@ import { Observable } from 'rxjs/Observable';
 import 'rxjs/add/operator/map';
 import { Http, Response, Headers, RequestOptions } from '@angular/http';
 
+
 @Injectable()
 export class ItemService {
   private apiUrl = 'http://localhost:3000/items';