To find the dealership that pays the most for used cars, research and compare offers from different dealerships. Some factors that can affect the amount you receive include the condition of the car, its age, and its mileage. You can also use online tools such as Kelley Blue Book to estimate your car's worth before you start negotiating with dealerships. Additionally, consider selling your car directly to a prospective buyer or using online platforms specializing in buying a used car for an instant cash offer.