You MAY use credit cards in the shops on the ship. My wife did this when she wanted to buy somethign for me on the ship to give to me later and not have it show up on the bill. The cast members said there was no problem using credit cards at all. If you want to put a limit on them I would call DCL and check to see if they accept prepaid credit cards as well. Like I siad, I do know that they accept regular credit cards for sure.
