I used to collect and flip baseball cards. Really enjoyed it when my boys were young but their grown and gone now.
The hobby was destroyed by the over production of cards by the manufacturer and ebay though still a pretty hot market is overrun with scammers and crap. I now have boxes of my best and most valuable stored away for my grandkids to have whaen their ready.
I have a few select cards and other items that are worth quite a bit but I find watching the game is much more enjoyable than trying to make money on it.
Anybody up for a hot dog and a beer!