How we know what we say we know.

Where the evidence comes from.

Results from auction houses worldwide, dealer and private transactions reported to STABLE with consent, completed sales on the Stable Marketplace, and current offerings. Every source is named on the comparable it produced. [SOURCE LIST TO BE CONFIRMED]

How the evidence becomes a value.

Comparables are weighted by similarity and recency; adjustments for condition, specification, mileage, provenance and documentation are estimated from the market’s own history; supply and velocity set direction. The model is reviewed by specialists for each segment.

Why every value has a range.

We publish an 80% range: we expect four in five sales of an equivalent car to fall within it. When evidence is thin, the range widens and the confidence level falls — we would rather be honest than precise.

What Declared, Documented and Verified mean.

Declared facts are entered by the owner. Documented facts have evidence in the Vault. Verified facts have been reviewed by a STABLE specialist against the car and its record, and are dated.

Values are not for sale.

[POLICY TO BE CONFIRMED] Stable Value is calculated the same way whether or not a car is offered on STABLE, and no seller, dealer or advertiser can pay to change it.

Your collection is yours.

Values, costs and documents are private by default. We do not sell data about you or your cars. Aggregated market statistics never identify a car or an owner.

Every change is on the record.

Methodology changes are published here with a date and an explanation. Individual values show their history, so you can see how and when they moved.