Many of you like to purchase additional car-rental coverage for peace of mind. But remember to always read the fine print—or you may end up voiding your policy altogether.

When you sign a “collision damage waiver” or “loss damage waiver” with a rental car company, you’re not really getting insurance—you’re getting a guarantee that the rental agency will cover damages.

But in exchange, you have to abide by certain rules.

There are some very common scenarios that can void your policy and leave you personally responsible for any costs.

That includes driving out of state without informing the company first, or violating the speed limit.

Other scenarios you may not have thought of include towing something behind your rental vehicle, like a boat or a trailer.

Even driving on unpaved roads can void the contract.

And, you know that rule about not letting someone who’s not on the policy drive the car?

Well, that can also include valets and parking attendants.

Bottom line: Restrictions vary between companies, so always read your contract.

If necessary, ask a rental agent to go through it with you to clarify what scenarios could nullify your rental contract.

For more, don’t miss our Driving & Rental Cars section.

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