Automatic deposit
At the top of the screen, give each offer the share of the price paid at booking (for example 30) and the number of days before the start at which the balance is due. Every booking made online for that offer then gets its deposit and balance schedule by itself: the visitor pays the deposit when booking (the form tells them), and the balance has its own payment link and due date.
You choose the deposit, never the visitor. Leave it empty, or at 100, for an offer paid in full. Bookings you enter yourself are not affected. It needs VEFmultiBooking (Free) 0.24.3 or later.
Schedules and requests
Search for a booking by its number to create a deposit and balance by hand, a split payment schedule (several equal installments) or a one-off payment request (any amount). Each installment has its own payment link, payable online, or recorded by hand (cash, transfer).
When a booking is cancelled or declined, its unpaid installments are cancelled with it: the links stop working and no reminder is sent.