Suggests the possibility of adding payment (in the form already available in the program - cash, PayPal...) as a prepayment from the customer.
- e.g. a new customer we do not trust makes a prepayment for remote assistance
- An existing customer makes a prepayment for the purchase of a license
That is, a customer with a pool of money based on which we later add a payment for the service on the invoice.
So each customer would have to have something like an account?
