Carvana provides a 7-day money-back guarantee on all cars they sell. In addition, they offer a 100-day limited warranty on their vehicles. This warranty applies 100 days or 4,189 miles from the time of purchase — whichever comes first. On top of their basic warranties, they also offer extended warranty options for purchase. You can choose to purchase extended coverage, or you can decline this coverage. The cost associated with the extended coverage will depend on the type of coverage as well as the age and mileage of the vehicle.