I found mydvc.com is updated with the reservation number and summary as soon as you make the reservation. So I just take a screen shot and email the renter a copy. I think Paypal offers some buyer protection also.
I would do my best to make a renter comfortable. But I would not work with someone is uncomfortable with the process in the first place.
Great idea!
The renter already paid me up front for everything without a contract, etc. I know the person. I just want them to feel extra comfortable.