I have a box of 20 year old baseball trading cards that I want to sell. I’m not sure about their value but I have cards like Barry Bonds and Mark Mcgwire.(from the late 1980’s) what could they be worth and how do I sell them on ebay? Is there a better place to sell them than Ebay?

A friend of mine recently came across a box of older (1980’s and on) baseball and other sports/trading cards. Most are well known brands (Topps, etc.) and almost all are sealed packages.

Other than searching through ebay for each individual pack/card/set, or trusting a local memorabilia dealer, is there an efficient way to find out if these cards are worth any value? Or would it be better to open the packs and search for uncommon cards?

My sister found a bunch of old baseball cards that her no-good fiance left at her house. She has a huge binder full and knows nothing about baseball. How would she go about finding their value without looking them up one by one on ebay? What shouldn’t she do?