What should my mares be used to when they go to the auction?

I was the "best answerer" of your last question and all I have to say is... Your horses are going not going to go to a good home the way they are. NOBODY is going to buy a pony you can't touch and good luck having people buying a horse you can't ride. Why don't you keep them a little longer and put ads on craigslist and dreamhorse and try to find them a good home? You could give the pony to a rescue so they can train her and maybe someone on craigslist would take your TB as a project horse. I probably would. But taking them to an auction WILL NOT end well for them. They will probably be bought by a kill buyer.