Many buyers treat a vehicle service contract as a standard part of the car sale, and never stop to ask whether it is actually required. Before you commit to anything, find out three things in writing: whether the contract is optional, what changes if you decline it, and whether you can buy one later on your own terms.
Ask whether it is optional
Ask the seller directly whether the contract is required to buy this car, to arrange the financing, or to take delivery. If the answer is no, ask for that answer in writing on the deal sheet. If the answer is yes, ask which document says so and which part of the sale depends on it. A verbal yes is not enough to rely on, because verbal answers are the first thing to disappear when a deal changes.
Ask what changes if you decline
Ask whether declining changes the car's sale price, the financing terms, the trade-in figure, or any other line in the deal. Ask the seller to write the answer on the deal sheet itself. Then compare that sheet with the sheet you were first shown, line by line, and mark every item that moved. A change that appears only after you say no is worth noting before you decide anything else.
Ask whether you can buy later
If you decline now, ask whether you can buy a contract for this car after the sale, either from the same seller or from a provider you choose yourself. Ask whether the terms or the availability change after a certain point in time, and get the cut-off described in writing. Do not sign just to meet a cut-off, and do not sign because the answer is vague. A vague answer is a reason to slow down.
Check the contract before you decide
Ask for a copy of the actual contract before you commit, not a summary or a brochure. Some providers publish a sample contract you can read first, and the published list on this site shows which ones do, so you can compare the wording before a salesperson sits across from you. If the seller refuses to let you read the contract before you commit, you have learned something about the deal, and it is reasonable to walk away and come back later with a copy in hand.
What to bring to the desk
Bring the sheets you have already been given, a pen, and a written list of the questions above. Mark each answer as you get it, and do not accept an answer you cannot see on paper. If the answers change between the first meeting and the last, you have the sheets to show what moved.