Support your diminished value claim with completed auction comps from nineteen major platforms. Appraisers need evidence - Old Cars Data gives them normalized market records.
400,000+ auction sales
Completed sales, not listing estimates
Updated every 15 minutes
Yesterday's auction activity available today
Nineteen sources
BaT, Cars & Bids, Mecum, Bonhams, SOMO, and more
Definition
Diminished value is the reduction in a vehicle's market value after it has been damaged and repaired, even if repairs restore it to pre-accident condition. Once a vehicle carries an accident history, its resale value decreases, and insurers may owe you compensation for that lost value.
To claim diminished value, you need evidence of your vehicle's pre-accident market value. Comparable sales data shows what similar vehicles actually sold for, providing objective proof for your claim.
Evidence
We provide evidence, not appraisals
Old Cars Data provides the market evidence appraisers need to support diminished value claims. We do not provide appraisals, legal advice, or insurance advice. When filing a claim, work with a licensed appraiser and share our comparable sales data with them to:
Access the data
Coverage from 2018 to present, refreshed every 15 minutes, across more than 400,000 auction sales.
Query auction data in plain English via MCP. No coding required. Perfect for appraisers and analysts.
Programmatic access to auction data. Perfect for developers and automated workflows.
Create a free account to access comparable sales data. No credit card required.
Diminished value data by model
Each model page includes recent auction sales and market context to support your claim.
"What did diminished value compss sell for last month?" - get answers in seconds. Ask about values, trends, comparisons, or anything you'd look up manually.
MCP prompt log
Trust & transparency
Old Cars Data provides market data only. This is not legal, appraisal, or insurance advice. Always consult licensed professionals when filing a diminished value claim.
Sourced from Bring a Trailer, Cars & Bids, Hemmings, AutoHunter, Hagerty, PCAR Market, All Collector Cars, Gooding & Co, RM Sotheby's, and Sotheby's Motorsport. All data represents actual completed sales, not estimates.
Reviewed by the Old Cars Data market data team. Data is updated every 15 minutes and verified against source platforms.
Reference notes
Diminished value is the reduction in a vehicle's market value after it has been damaged and repaired, even when repairs restore it to pre-accident condition, because the vehicle now carries an accident history.
Work with a licensed appraiser in your area and provide them with comparable sales evidence. Old Cars Data supplies the normalized auction comps an appraiser can use to calculate accurate diminished value.
Insurance companies require objective evidence. Comparable sales show what similar vehicles actually sold for, providing concrete proof of pre-accident market value rather than estimates.
Pull comparable sales for your make, model, year, and condition through the API or MCP server, then share those records with your appraiser to support their calculations.
Bring a Trailer, Cars & Bids, Hemmings, AutoHunter, Hagerty, PCAR Market, All Collector Cars, Gooding & Co, RM Sotheby's, Barrett-Jackson, Sotheby's Motorsport, Car & Classic, The Market, Broad Arrow, MB Market, Mecum Auctions, PistonHeads, Collecting Cars, and Bonhams.
Every 15 minutes. New completed auctions are ingested and normalized throughout the day.
Coverage runs from 2018 to the present across more than 400,000 completed auction sales.
Through the MCP server inside ChatGPT and Claude, or programmatically through the REST API with a free API key.
No. Old Cars Data provides market data only. Always consult licensed professionals - appraisers, attorneys, and insurance experts - when filing a claim.
Yes. The comparable sales records are designed to serve as objective evidence that appraisers and claimants can present to support a diminished value claim.