It's usually a good idea to compare the odometer reading with the "out" mileage on your contract when you pick up the car. If there's a discrepancy, address it before you drive away. And always take a photo of the odometer reading and fuel level when you return the car, and make sure that the "in" mileage on the contract is correct. If you do not get -- and check -- a return receipt when you return the car, you're just asking for trouble.

Mistakes happen. You've got to take some steps to protect yourself.

If your dispute with Amex is upheld, why would you be charged any interest on an incorrect charge?​​​​​​