Search supported Buy It Now singles on eBay and Mercari, then compare asking prices with available market references. Coverage depends on the listing, source access, and any paid data services you configure.
Paste an eBay / Mercari title (and URL if you have it), or just search a card. Marketplaces block automated page reads, so the title and ask are what we match.
One desk’s snapshot. Open a card for the full book — Cardmarket, solds, PriceCharting.