the only minor thing that the person who offered did wrrong was to say "If you're flexible at all, I'll buy the dimes.." Whjile not directly insulting, it gives a certain tone to the whole message.
I have heard of people offerring less than face for coins, so if you got a low ball offer, do not feel singled out, everybody has had offers that were less than fair. Take it with a grain of salt.
I'll just put it out there: I was his first offer @ $82 (when silver was at $40-41ish). I figured in the price of silver though, not the clad stuff that was on there (not paying for pocket change), nor the folder. @ $41 it would've been around $94 in silver. but considering I just sold $3.10 face for $80, I felt $82 was fair. stainless