The current market value of a used vehicle is determined by its production year , features , mileage , and overall condition . The insurance company comes up with a dollar amount that is supposed to represent what you can go and buy off a lot less the lot ' s profit to replace the vehicle you had in your possession 1 minute before your crash . If you feel you can ' t purchase a replacement for the amount they offer you , you can obtain proof by providing the insurance company with usedcar sale ads showing what they are charging , and you can should be able to negotiate that with your insurance company . Also , negotiating goes a lot better with your own insurance carrier rather than the one of the guy who hit you . While they may be liable , you don ' t pay them so they really don ' t give a shit about you and will lowball the fuck out of you .