This is a great thread.
Personally, I went to a Rothstein show in White Plains one year maybe 15 years ago, and a guy was complaining that the show was so bad, he hadn't made his table fees. He had a big stack of EX-MT T206s, and when I asked to see them, he said "Everything in that pile, twenty bucks each." I pulled out five cards including a Waddell portrait, paid the man $100, and walked away smiling.
I later lost the Waddell, sadly. No idea where it is.
Professionally, I recently received a consignment of tobacco cards from the family of the original owner that included 13 N172s (7 HOFers), 80 or so T205s, about 280 T206s including a bunch of Cycle and AB 460s, about 80 T207s including a Red Cycle, a bunch of Broadleaf and a Ward Miller, and a bunch of 1920s strip cards. The couple who consigned them were lovely people, and really didn't know what they had. They had run into an unexpected home repair bill that was going to cost them a thousand dollars, and they asked me if I thought there was enough value in the cards to cover the cost. I reckon they'll be pretty happy with the result.
-Al