I'm relatively new to this, so I might just be missing how to do this. Let's say I have a single card that I want to add to a collection for trade. Let's say Tim Costo's 1991 Gold Leaf Rookie #BC18. On beckett.com, I'd type "Costo BC18" and it would find all the cards that match those two search terms. In this case, it would just return the one card and I could then add it to my trade collection.
From what I can tell here, I would either search for the set "1991 Leaf Gold Rookies", find the checklist, search through to find my card, then add it for trade. Or, I could go to Tim Costo's page and find it a couple of different ways. When entering a bunch of cards, it would be easier to perform one step to find a card, rather than drill down multiple pages to get to what I want.
Any help is appreciated! I'm enjoying this site, and it really does provide lots of neat things for the player collector. Thanks!