I need to be able to receive payment for events that might end up being more than the invoice total. For some of our facilities, if the client is new, we request 100% deposit of the anticipated charges. If the client is in the space less than anticipated, they would be due a refund. Currently, I am invoicing for these events after the fact and not ahead of time. While I understand we would not process the actual refund in the system, I would like a clean audit trail for all money to be accounted for.