The fair market value of a car can be determined based on the year, make, model, mileage and condition of the vehicle. The car's history can also greatly alter its fair market value. The Kelley Blue Book is a great resource for accurately determining your car's fair market value.
When determining the fair market value of a car, it is important to have details regarding the car's usage and accident history. If the car has surface damage from a collision, or interior damage from flooding or improper care, then the value of the car goes down. It is also ideal to note any mechanical or part failures.