General Forum

Does anyone have an idea for establishing the value of cards? For example, if I own a card with serial number 1 of 1, that I pulled from a pack/box, where does it's value come from since it hasn't been sold individually?

Check Ebay for other low serial number of that player and check other 1 of 1 cards from that set of players that are at a similar level to the player you have. Make sure to check sold listings not just currently open auctions. 

To me, a 1/1 is worth what someone is willing to pay for it, the better the player of course the more $$$$$. I would imagine you could look for other similar cards that sold already from comparable sets, and depending on the player, even diff. years.

My best pull was a 1/5 var. of a 1/10 triple flag card of my fav. driver, Jeff Gordon, no values in bk. due to scarcity for either, its worth $300 to me if i had to part with it 

But it did have to start somewhere ... the value that is 

For something rare, I find real comparisons. If the same player has multiple versions of the same card with different SN's, look at all the versions and compare the book value and/or sell prices. You'll be able to figure out a multiplier for each level and then you can come up with a reasonable value or selling price for the rare card. That's how I've done it for decades. If there are no comparisons for the same card, then you use the methods above (similar player and/or set).