A merchant-model booking is paid to the agent before the guest arrives. The property has money coming, a guest who owes nothing for the room, and a bill that still has to foot.
The prepayment is treated as an ordinary deposit receipt, tagged with the booking channel and tendered as an online payment so no drawer moves. It then rides the existing transfer-at-check-in path onto the stay folio.
That reuse is deliberate rather than lazy. Inventing a parallel primitive for OTA money would mean a second billing path to reconcile, whereas the deposit ledger already knows how to hold money that belongs to a guest and move it onto their bill.
On the bill the credit line reads as what it is — prepaid via the named agent rather than a bare "deposit received" — because the guest should recognise their own transaction.