Once the real costs can be charged, the deposit paid by the guest on forehand should be settled with the costs to be paid.
01. Book deposit/advance payment reverse
To settle the deposit/advanced payment the guest already paid for, an add-on has to be added to the reservation having the value in negative of the deposit/advanced payment that's already in the reservation.
In Newyse, this easily could be done in CICO as well on Check-out by adding the same extra for number = -1. In MXTS it's not possible to add an add-on for a negative number. So a new add-on should be created having a reate of -€75 in this example.
In this example, both are the same add-ons, because I first did it in Newyse. When a new add-on is created for the reverse booking, they won't be netted on the bill.