After you agree on a price, you'll usually sit down with someone who handles the paperwork. This is often where extra products appear, such as extended service contracts, paint and fabric protection, window etching, tire and wheel plans and gap coverage.

Some of these may be useful for certain buyers, but they're frequently priced with a large markup and often rolled into the loan, where you'll pay interest on them for years. They may also be presented quickly, as if they're a standard part of the deal. They generally aren't required to get a loan, and you can decline them.

Ask for a written list of every add-on and its price, and take time to read the terms. If something interests you, you can usually buy similar coverage elsewhere, sometimes for less, including gap coverage through some insurers or lenders. Review the final contract line by line before signing and make sure nothing has been added that you didn't agree to.