What Would You Do If Facing This Situation?

Here is a similar situation, I went to a general esttate auction 5 years ago, looking for stamps, because the auctioneer would show what was going up for auction on the web site AuctionZip.com.
There was something that looked interesting to me.
I got there late, and only had a few minutes to look over what was a lot of 4 Xerox boxes of all kinds of stamps, and stamp gauges, and magnifying glasses and glassines.
Long story short, I wanted this lot.
It went up and I got all 4 boxes for $110.00
That was 5 years ago, and I am still selling off items that were in that lot. So far to a profit of over $3,000 so what should I do, go back to the auctioneer and say I owe you more money.
NO buying at auction is always a crap shoot, sometimes you win and sometimes you lose.
Pay what the guy asked for and add to your collection and or sell what you do not want.

postalpicker,

No one could expect further contact after an auction purchase, especially if it was available for review ahead of time.

Neither would one have qualms about cherry-picking a professional dealer - for they should "know" better... This happens all the time, in numismatics as well as philately.

In the scenario given, I would feel uncomfortable possibly taking advantage of a clueless seller. Others would have no qualms about it, obviously. That is exactly the ethics issue. I suppose each buyer would deal with it in their own way.

All IMHO, obviously.

John