You draw the line where the line is obvious. It's obvious a general auction like the one that started this thread is going to have enough attendance without further blabbing about it that everything will sell at above scrap value no matter what. (esp in the DC area where machinery tends to sell high anyway)

And yet when one or a few old, ugly and/or heavy machines show on Craiglist priced at less than scrap value sitting in the middle of nowhere in Kansas, it's equally obvious that they may not sell and hence chatting about them here is ok.