I'm quite new to selling, but if you have a Paypal account then that seems to work ok for paying your sellers fees. I did need a credit card though as I was scheduling something to start selling at a different time to when I was actually putting it into the 'puter (Thurs 9pm, 5 day listing, therefore finishing at 9pm on Sun - good time!)
It seems to be an insurance in case you don't pay your bills and they have another way of getting the money off you.
hth - confused myself there I think!