A few people can explain a service contract to you: the seller's finance office, an outside helper you hire, or you, with the document and a pen. Each can be useful. Each also has a reason to present the product in its most attractive light. Your job is to decide who is checking the terms, and then to check the parts that matter yourself.
What the seller's walkthrough is good for
The finance office can tell you the process, the order of the paperwork, and how a claim is usually started. Ask them to explain it in plain language, then ask what happens if you want to cancel. Write down the answers. If the explanation changes when you ask the same question twice, you have learned something about the contract.
What a paid outside reviewer should answer
Some buyers bring in an independent reviewer. Before you hire one, ask whether they earn anything from the contract you buy, whether they sell or represent any provider, and how they are paid for the review. An answer that leaves out the payment structure is a reason to keep looking. Ask whether they will read the exclusions, the claim route, the cancellation rule, and the transfer rule with you, and whether you will keep a copy of their notes.
What to check yourself, no matter who explains
Read the exclusions before the coverage summary. Find the claim route: whether you call the provider first, whether the shop must be approved before work starts, and whether the provider pays the shop or you pay and then ask for reimbursement. Find the cancellation section, and note whether the refund goes to you, to the lender, or to the seller. Find the transfer section, since a sale of the car may or may not carry the contract with it. Check any age and mileage limits against the car you own, not the car in the brochure.
Buying direct or through the seller changes the questions
When you buy through a dealer, the contract may be sold by one company and administered by another. When you buy direct, the company you pay is often the one that handles your claim. The direct providers that administer their own claims page lists companies that run their own claims, which can make the question of who answers the phone easier to settle before you sign.
When to stop and get outside help
If the contract is confusing, if the claim route is unclear, or if the seller will not let you take a copy home, slow down. This is general information, not legal advice. A consumer protection office or an attorney in your state can explain your rights under your own jurisdiction's rules. Get that answer before you hand over any deposit.