Two things:

* User views its devices, from a /manage index link
* Yavsc.Server resurection

Yavsc.Server/Models/Billing/ProportionalImpacter.cs

@@ -0,0 +1,13 @@
+using Yavsc.Billing;
+
+namespace Yavsc.Models.Billing   {
+    public class ProportionalImpacter : IBillingImpacter
+    {
+        public decimal K { get; set; }
+        public decimal Impact(decimal orgValue)
+        {
+            return orgValue * K;
+        }
+    }
+
+}