It is not infrequent that we receive a question from a customer - the guest checked in and said they paid Expedia/Travelocity/etc and they don't need to pay me. Is this correct?
The answer to this question is simple: If you have NOT signed a specific contract with a third party Online Travel Agency (OTA) website such as Expedia, Priceline, or Orbitz, then the guest who booked DID NOT PAY. They may have been forced to enter their credit card to meet your deposit policy, but the Online Travel Agency (OTA) such as Expedia, Priceline, or Orbitz did not charge them. The guest has likely been charged 'at time of booking' in the past, and thus assumes it happened again. If this is the case, offer your phone to the guest, have them call the website (such as Expedia or Orbitz) and confirm this is the case, so that all is well between the two of you. Then they will feel fine giving you their credit card and paying for this hospitality.
If you DID sign a specific contract with a third party Online Travel Agency (OTA) website such as Expedia, Priceline, or Orbitz, then it is possible that there was a pre-payment by the Guest. BookingCenter WILL NOT know this, as only your contract with that third party can define the payment relationship between the OTA and your business. However, some of our customers do participate in these 'pre payment' models known as Net Rate or Merchant Model programs (as explained at: http://www.bookingcenter.com/products/net_rate.html) and only your contract, or your account representative with the OTA, can inform you of the pre-payment terms the customer paid. Most Net Rate relationships deliver the credit crd from the OTA with the booking, for you to charge at check out.