Heh, my friend got his xbox modded at an independent videogame store once. Didn't pay. He easily got away with it cause it's not like they can call the police. One call to the Better Business Bureau and there goes their business.
It didn't go through on his debit card (he put a bend in his debit card so it says 'approved' but doesn't charge him, works 30% of the time), and when they called him for the money, and he just never went there ever again.
And yeah, he's a jerk. He's also on this board, heh.