To operate the THOR online reservation system does not mean that you have to take advance payments or deposit.
You, like many accommodation providers, may prefer to take customers on trust that they will turn up on the agreed date and time – so you can use the online reservation system in the same way that you agree a booking on the telephone without money changing hands.
However, customers are becoming more used to the idea of making a deposit. Moreover, it gives them more confidence that a reservation has indeed been made and that they will not be turned away on arrival.
Modern banking methods and the widespread use of credit/debit cards give rise to several options which may be used in conjunction with the THOR reservations system. Note that THOR does not take online payments itself but is a facilitator of payment by customer to accommodation provider.
You can set up THOR to operate with several methods at the same time.