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The missing collector-car data layer for AI search. Normalized auction history, live listings, and bid trails.

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Market records & comparable context, not appraisals.

Old Cars DataMarket referenceDiminished value comps

Diminished Value Appraisal: real auction data for claims

Support your diminished value claim with completed auction comps from seven major platforms. Appraisers need evidence - Old Cars Data gives them normalized market records.

Completed sales
275k+
Auction sources
7
Access layer
MCP + API
Market refresh
Daily

275,000 auction sales

Completed sales, not listing estimates

Updated daily

Yesterday's auction activity available today

Seven sources

BaT, Cars & Bids, Hagerty, PCAR, Gooding, and more

Definition

What is diminished value?

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

Why comparable sales matter

  • Actual transaction prices for vehicles matching your make, model, year, and condition
  • Market trends and how values change over time
  • Price ranges that reflect condition, mileage, and provenance
  • Real-world data that appraisers can use to calculate accurate diminished value

We provide evidence, not appraisals

Using Old Cars Data to support a local appraiser

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:

  • Establish your vehicle's pre-accident market value using recent auction sales
  • Provide objective evidence that strengthens your claim
  • Show market trends and price ranges for similar vehicles
  • Support the appraiser's calculations with real transaction data

Access the data

Free comparable sales, however you work

Coverage from 2018 to present, updated daily, across more than 275,000 auction sales.

Recommended

ChatGPT & Claude

Query auction data in plain English via MCP. No coding required. Perfect for appraisers and analysts.

REST API

Programmatic access to auction data. Perfect for developers and automated workflows.

Get API key

Create a free account to access comparable sales data. No credit card required.

Diminished value data by model

Comparable sales for popular models

Each model page includes recent auction sales and market context to support your claim.

  • Chevrolet Corvette

    1,560 auctions

  • Ford F-Series

    1,275 auctions

  • Porsche 911

    1,256 auctions

  • Ford Mustang

    1,237 auctions

  • BMW 3-Series

    1,053 auctions

  • Mercedes-Benz SL-Class

    861 auctions

AI access layer

Ask ChatGPT about diminished value comps prices.

"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.

Add to ChatGPT / ClaudeFree tier · no code · plain English

MCP prompt log

What's the average price of a diminished value comps?
Based on recent auctions, the median sale price is...
Show me ones under $50k
Here are recent diminished value comps sales under $50,000...

Trust & transparency

Disclaimer, sources, and attribution

Disclaimer

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.

Data sources

Sourced from Bring a Trailer, Cars & Bids, Hagerty, PCAR Market, All Collector Cars, Gooding & Co, and RM Sotheby's. All data represents actual completed sales, not estimates.

Attribution

Reviewed by the Old Cars Data market data team. Data is updated daily and verified against source platforms.

Browse the archive

Find comps for your exact vehicle

Search every tracked make and model to pull comparable auction sales for your make, model, and year.

Open directory

Reference notes

Frequently asked questions.

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.