A certified vehicle generally extends the factory warranty. Keep in mind though, the factory warranty generally only covers defects. This is where a lot of people get confused. Service contracts, often mistakenly called extended warranty, is an insurance plan against something breaking. You are betting that the $3,000 service contract is going to cost you less than whatever repairs the vehicle will require during the life of said service contract. The service contract company is betting on the opposite. They also don't pay full retail for repairs and they don't pay $140 per flag hour.