Haha. Well, if this is a case where you think this deal is going to go south on you (from Apple's perspective), my advice would be to use the money up right away and then try a different auction for your "play" money.
ie: Buy a couple TV seasons in HD or something. Then go for another (safer) auction if you just want some money in the account for renting a movie now and then.
Edit: I probably could have (and should have) posted my experiences with this stuff earlier. My apologies if I could have saved you from buying this auction in the first place.