Book query tracking

Yavsc/Models/Billing/Query.cs

@@ -1,11 +1,32 @@
+using System;
 using Yavsc.Interfaces.Workflow;
 using Yavsc.Models.Market;
 
 namespace Yavsc.Models.Billing
 {
 
-    public class Query<P> where P : BaseProduct
+    public class Query<P>: IBaseTrackedEntity  where P : BaseProduct
     {
+        public DateTime DateCreated
+        {
+            get; set;
+        }
+
+        public DateTime DateModified
+        {
+             get; set;
+        }
+
+        public string UserCreated
+        {
+             get; set;
+        }
+
+        public string UserModified
+        {
+             get; set;
+        }
+
         QueryStatus Status { get; set; }
     }