We have studied on the default prepayment function in the Sales Order but found that it can only apply to one invoice. But in our situation, we receive a lum sum prepayment from customers before issue Sales order. And deduct the prepayment from the invoices later on. Does anyone know that how to perform in NAV? We tried to issue a “manual” payment invoice by selecting a prepayment g/l account to the item line in the sales invoice. And deduct the same g/l account when issue Sales Invoice. But there is no report/screen can shows the balance breakdown of the g/l account, we must keep track to how much prepayment is used for each customer.