You may be charged the deductible for every part repaired. If you buy direct, you avoid dealer markups. Be sure to get quotes from sources other than your dealer. The dealer's business manager may make you feel like a fool if you don't buy an extended warranty, some unscrupulous dealerships may even insist upon it if you're financing the vehicle through them. Typically, the salesperson gets a flat fee and the balance of the profit goes to the dealer.
Salesmen can make more money selling extended warranties than they can selling cars.
That's why I can't recommend buying an extended warranty at the dealer. There are a lot of people making a lot of money selling inferior products. There are a lot of people making a lot of money selling inferior products. There are over 50 extended warranty companies to chose from. I spent two weeks researching the warranties available from reputable vendors, carefully comparing the coverage and the costs for each one.