Current collectible trading card price estimates are produced by running data (auction prices from trading card consignment services) through a statistical m0del of my making. Crucially, these predictions will evolve — for the better, I hope — as more data gets fed into the models.
You will find data on traditional sport card categories of Baseball cards (MLB); Basketball (NBA); Football (NFL); and Hockey cards (NHL); but also for relatively smaller sport card collecting communities of Soccer (Bundesliga, Premier); Golf (PGA); Tennis; MMA; Boxing; Racing; etc. in addition to non-sport gaming cards such as Pokemon; Magic; Yu-Gi-Oh; Digimon; Wizards of the Coast; Star Trek; Star Wars; Marvel; etc.