Thanks all around, guys.
Art, as to the above quote, do you tell them what you'll offer first? Or do you ask what they want?
That's my problem. I don't tell them up front. I'm worried I'll either overshoot the ask (and get ripped off) or undershoot and offend them. Instead, I have them tell me the price. I don't know if the ask is their lowest or if they want to see if I'll haggle.
The only way to fix this is better education of the value of the coin. Somehow I need to find the value of scarcer coins/notes with a smaller market.