Sure, it's nice and convenient to step off a plane and straight into a car, but it's worth doing some investigation to see how much you're paying for the privilege. It's definitely a good idea to check if the rental company charges an "airport fee" and compare prices with other local firms. Ask yourself if you need the car straight away, too. Sometimes it's just as easy to use the hotel shuttle service and collect your car at a later date from a cheaper outlet. You often can't look past the convenience of the airport rental as well, so shop around and don't just plonk your credit card down on the first one you see.