public void TestAddOfficeSubscription()
        {
            //Arrange
            Guid cID   = clist.FirstOrDefault().ClientID;
            Guid SubID = Guid.NewGuid();

            //Act
            Cservice.AddOfficeSubscription(cID, SubID, 10);

            //Assert
            Assert.AreEqual(SubID, clist.Find(c => c.ClientID == cID).ClientSubscriptions.FirstOrDefault().SubscriptionID);
            Assert.AreEqual(10, clist.Find(c => c.ClientID == cID).ClientSubscriptions.FirstOrDefault().UsersPerSubscription);
        }