This is a topic that I have been thinking more and more about, I am really thinking that I need to have a "formula" or "algorithm" that helps assign a "value to a card. For years, I have always said book value should be fine as long as both parties agree to that. So if you are trading $50 in book for $50 in book, that is fair. Now of course that all breaks down when a player is hot or the product is new, etc. I have also used the HI Book x 33.33% = my buy price. That tends to be pretty much what eBay comes out to anyhow, and I am happy with that most of the time.
What has been getting me is people decide what to use only when it benefits them, is it eBay, COMC, Beckett? Honestly they are all flawed, but I am really thinking it is time to get some parameters around it all. Guess I will hold that for another post later.....