Posted By:
runscottI've warned friends before that their BIN's were too low, but I wouldn't warn a self-proclaimed expert.
I agree with Jeff O that the seller has a responsibility to do just a little research first - if they don't know what they're selling, they can omit the BIN and let the market determine the value.
On the other hand, when you see an obvious case of a novice collector about to be screwed, you need to do something. At this year's National I was walking from the train station to the convention and a slightly mentally challenged man (50ish guy) with a brown paper bag latched onto me. He had loads of mid-60's HOF'er cards just tossed into this bag (no protection at all), and was going to take them to a dealer table and sell them. He was very excited. I had to explain to him that a dealer might (boy am I being nice!) take advantage of him. I then gave him a top-loader for the NM '68 Mantle that was bouncing around in his bag, told him under no circumstances to take less than $100 for it, and directed him to a friend's table. I don't know what happened, but hopefully it was okay. I would have made him an offer (and I'm sure he would have taken anything), but I really didn't trust myself not to take advantage of the situation.