Here's how I've implemented the pre-paid support scheme in Billings. I was wondering if there was any easier way to do this. I'd be interesting in finding out how others are managing prepaid accounts.
I create the new project; add a payment for the prepaid amount. As support calls are made, I add time slips to the Working Slips tab. The prepaid amount is visible at all time in the balance located at the top on the project line. This makes it easy to know how much time he has left. My rates are $30 per hour. The individual slips get assigned a monetary value for the time spent on each support call...
