In truth, the best way to buy a used car is to purchase it from a friend, a relative, a co-worker that you know well and trust. In this way, you should have full access to the vehicle history. You can learn first hand about any accidents, breakdowns, major repairs, and how well was the vehicle maintained?
The great majority of Buyers will research online for the year, make and model that will best sit their needs. Do not let price be the determining factor. The vehicle with the lowest price is probably low for a good reason. Price is important, but value and condition are much more important.
Where is the vehicle (and the dealer) located? Is it 10 miles away or 100 miles? If you need to return the vehicle for a needed adjustment or repair, will it be convenient, or will it be a hassle?
The selection of the dealer is just as important as the car itself. Does the dealer have a good reputation? Does he have lots of positive reviews posted at third party sites. Does he offer a large selection and convenient financing terms? Does the vehicle come with any warranty or extra benefits? How long has the dealer been in business?
All used cars and trucks are unique. There are no two that are exactly alike. One cannot assume anything about a used vehicle. You have to see it and drive it to make a good purchase decision.