In my restaurant the waitress put an order in and at the end gives a bill to the customer and the customer pays at the register on the way out. When customers bring the check to pay at the cashier, the discount functions are locked.
Thanks for the help.
If anyone wants to do something similar. I have a cashier screen set up and set it to display tickets and go directly to payment screen. I simply added an unlock ticket action to the cashier screen rules