Base comparable
Every item begins with a base comparable value drawn from representative sales on eBay, Heritage Auctions, PSA, Chrono24, AbeBooks, and Christie’s. Where sources disagree, the median of recent sales wins.
About
PROVENANCE is a collection inventory and valuation platform for rare book, trading card, print, and watch collectors.
It records what you own, what you paid, the condition it is in, and where it came from, then values the whole collection continuously against comparable market sales. Insurers, appraisers, and estate executors receive a file they can act on rather than a folder of receipts.
Founded2023
Categories supported4
Comp sources6 tracked
Report typesInsurance, estate, tax
Methodology
How PROVENANCE arrives at a value
A valuation is only as good as its stated method. Ours is four steps: take a base comparable from representative sales, apply the category condition multiplier, weight it for documented provenance, then recalculate as new comps land while preserving the history.
Condition multiplier
The base value is multiplied by a condition or grade factor specific to the category. PSA 10 carries roughly 3.4x over PSA 8. A Near Fine rare book in jacket carries 1.45x. A full-set watch carries 1.25x.
Provenance weighting
Association copies, original box and papers, documented servicing, and authenticated signatures each shift value beyond condition alone, and each is recorded as a dated event so the reason is auditable.
Recalculation
Values recalculate as new comps arrive. History is never overwritten, so you can see what the ledger said last month and why it changed.
Who uses it
Collectors, estates, and dealer inventories
The platform serves three groups: individual collectors tracking a personal collection, estates and family offices settling or insuring a collection, and dealers managing consignment inventory that needs prices an appraiser will accept.
Individual collectors
Track a personal collection across all four categories, watch for comps, and know precisely what to declare at renewal.
Estates and family offices
Produce an estate inventory with a full provenance timeline per object, so an executor or an heir inherits the story as well as the asset.
Dealers and consignors
Maintain inventory with condition multipliers attached, and generate a tax lot schedule that survives an audit.
Privacy
What happens to the data you enter
In this deployment the workspace runs entirely in your browser and persists to local storage on your device. Nothing you enter is uploaded, transmitted, or shared, and clearing your browser storage removes it completely.
Where entries live
Items, provenance events, documents, alert rules, and profile settings are written to local storage under a single key on your device. Uploaded files are held as in-memory object URLs for the length of your session and are never sent anywhere.
Market data
Valuation history and comparable sales in this demonstration workspace are representative seeded data generated from published market ranges, not live feeds. Do not use them as the basis of an actual insurance declaration.
Terms
Demonstration workspace terms
This build is a demonstration. It is provided as is, without warranty, and it does not constitute an appraisal, a tax opinion, or investment advice. Any figure generated here is illustrative.
Disclosures
Valuation limits you should know
PROVENANCE produces fair market estimates from comparable sales and condition factors. It is not a substitute for a certified appraiser where a carrier, court, or tax authority requires a signed valuation.
- Condition factors are category baselines. An individual object’s defects, restoration, or unseen damage can move value well outside the applied range.
- Comparable sales are historical. A thin market with few recent sales produces a wider valuation range than the single figure shown.
- Insurance carriers may require an appraisal by a certified member of a recognised appraisal association above certain declared values.
- Tax lot output reflects recorded acquisition dates and cost basis you supply. It is not tax advice.
Questions about methodology or the demonstration data? Write to concierge@provenance.app or review the machine-readable summary at /llms.txt.