This almost happened to us last year. We had our room cards set up so we could charge things to the room, and at the end of your stay, they do one BIG charge to your card and if you have a dollar limit, as most debit cards do, it will NOT go through, no matter how much money you have in there. This annoyed me because I went to my bank before my trip and asked to have my daily limit raised or removed, and the lady at the bank told me I wouldn't have any problems since they (Disney) would be charging me each day, and not one lump sum. Well, she was wrong and good thing we had another credit card to use because we put EVERYTHING on our room card and had a big grand total at the end!