What is Diminished Value? ..Diminished Value is the reduced value of a vehicle after it has been repaired after an accident. In some cases as high a 25% of the vehicle value. What people don't know is you are entitled to the reduction in value from your insurance company. At Vintage Auto Appraisal we are experts in Diminished Value. Logging 1000's of research and auction hours. This has provided us with one of the world's largest Diminished Value Data Banks. Don't sell yourself short after a collision repair. Get A Vintage Auto Appraisal Diminished Value Appraisal and get the Diminished Value you are entitled to..