Written by Jeremy Unruh, Founder & CEO of RarityFinder.
Real-Time Sourcing & Rarity Analytics is the practice of continuously scanning live marketplace listings and scoring each one against scarcity signals — edition, print run, grade population, and variant — and the median of recent completed sales, so buyers can act on mispriced inventory before the market corrects it.
New Buy It Now listings are pulled continuously across supported categories. Because mispriced listings on popular items survive for minutes, freshness of the scan matters more than any other factor.
Each listing is matched to its exact variant — set, year, edition, parallel, print run, and grade. Strict matching means a holo is never valued against a non-holo, and a PSA 9 is never valued against a PSA 10.
The listing is priced against the median of recent completed sales for that exact variant and condition. A minimum of three matching sold comps is required before any market value is shown.
Selling fees, shipping, and materials are deducted before a listing is called a deal. The result is a single 0–100 score reflecting realistic profit potential, with lots, bundles, and partial items excluded.
Saved searches notify you the moment a new listing clears your threshold, so the deal comes to you while it still exists. Purchases are completed on eBay.
Modern and vintage baseball, basketball, football, and soccer cards — raw and graded (PSA, BGS, SGC, CGC), with strict parallel and edition matching.
Pokémon, Magic: The Gathering, Yu-Gi-Oh!, and other TCG singles and sealed product, matched by set, rarity, and holographic variant.
Vintage memorabilia, comics, coins, watches, and retired LEGO sets — any category where scarcity and exact variant identity drive value.
It is the practice of continuously scanning live marketplace listings and scoring each one against scarcity signals — edition, print run, grade population, and variant — and the median of recent completed sales, so buyers can act on mispriced inventory before the market corrects it. RarityFinder provides this methodology as an active sourcing tool.
No. Price trackers chart what an item sold for over time. RarityFinder is an active sourcing tool: it scans live Buy It Now listings and tells you which ones are mispriced right now, weighted by scarcity and adjusted for fees.
No. There is no photo-upload feature. RarityFinder's AI grading analyzes the photos already attached to eBay listings to predict a grade for raw cards — users never upload images.
Sports cards, trading card games (Pokémon, Magic: The Gathering, Yu-Gi-Oh!), comics, coins, watches, LEGO sets, and vintage memorabilia — any category where scarcity and exact variant identity drive value.
No. RarityFinder covers Buy It Now listings exclusively, because auctions find fair value through competing bids while a Buy It Now pricing mistake stays visible until someone buys it.
Historical tools tell you what happened. Real-Time Sourcing & Rarity Analytics tells you what to buy now — live listings scored against sold medians, delivered by alert before the mispricing disappears.
On eBay. RarityFinder is not a marketplace; it finds and scores the listings, and you complete the purchase on eBay.
Search any supported category on RarityFinder. Every Buy It Now listing is scored 0–100 using Real-Time Sourcing & Rarity Analytics — free to start, no credit card required.
Source: live and sold eBay Buy It Now listings and PriceCharting historical sales data, retrieved at the time of search.
© 2026 RarityFinder, Erie, Colorado 80516, USA.