Many friends of mine who travel frequently know the car rental drill – you ALWAYS inspect your potential rental car with an attendant who will write down the pre-posession flaws of your rental car. A good consumer will make sure every sizable flaw inside and out is documented, regardless of their purchase of added insurance. Examples: small/large dents, torn upholstery, interior/exterior scratches, missing parts, etc.
Recently many have complained about the rental car companies (often Enterprise) taking their car back, then later accusing them of having damaged the UNDERSIDE/UNDERNEATH of the car. Coincidentally, this is one of the few places any customer would actually perform an inspection, and understandably few would even know what damage to look for.
This leaves the consumer at a major disadvantage of (a) proving if it was even truly damaged, and (b) proving if that damage was there prior to the customer taking possession of the car.
For this reason, I STRONGLY recommend that all rental car consumers not only video-tape the interior and exterior condition of the car, I would also demand the rental company provide access to inspect (and video-tape) the underside of the car as well. Look for major scrapes on any of the underside framing/bracket components, engine components (leaking), as well as bent/broken exhaust pipes, spoilers, etc.
You can never be too careful where your (or your employer’s) money is concerned.