<prompt> Human: My new Prius of less than 7 months with less than 6 thousand miles was rear ended on the highway. I have not finished financing the car yet. There is frame damage, as well as under carriage damage, front bumper scratches, and broken rear bumper. The air bags were not deployed. The automatic braking system kicked in despite having the foot on the brake and it was a hard enough impact from the car to push my Prius into the car in front. The other party was entirely at fault and their insurance company is paying for the repairs.However, now I have this blemished carfax on my near brand new car. We brought my car to a Toyota dealer to be repaired. The gentleman in collision stated that I could bring the carfax to financing to refinance the car for the depreciated value. Is that considered a under water car loan? Can I do that? It sounded odd to me because the dealer shouldnt be responsible for someone elses negligence. I also googled diminishing value. Would that be better route to go? Are any of these option even plausible? I dont want to finance my cars full value when its no longer worth that value due to someone elses fault.  <response>: I went through a similar process when my 2016 Accord was a few months old and was rear ended with only 2000 miles on the odometer. The person who hit my car did approximately 5000 damage, but it was mostly superficial. I found an appraiser with a lot of experience with diminished value. After my car was repaired, I met with him for over an hour while he examined my car and took a lot of photos. He than researched what cars similar to mine without damage had been selling for throughout the country and in a few weeks he had a detailed diminished value report for me. He determined that there was about 4500 worth of diminished value.I submitted the report to the drivers insurance company Geico and they tried low-balling me. At first they would only pay out 1000 and than jumped to 2600 when I wouldnt settle. I ended up taking them to small claims court and represented myself. I was sure that Geico would settle prior, but we ended going to court. I was nervous but handed the judge a copy of the detailed diminished value report and I won the full amount since Geico didnt have competing reportappraisal of my vehicle. Definitely talk to someone with experience writing up diminished value reports. It may cost you a couple hundred for the report, but it will be worth it. 