Originally Posted by gpburdell
Suggestion: Use a credit card that allows generating a single-use credit card number with the charge limit you specify. Then you're doubly protected; the vendor you give it to can't charge more than the limit you set and the cc number will be denied if it's used again somewhere else. If you return the item, the company that made the charge can issue a refund to the number, but otherwise the number is one-and-done.
I always have a prepaid cc for buys like these...