There should be very little left as an auctioneer will bundle stuff that does not sell into larger lot with other items. The problem is some people will not take all they buy. They may want one item out of a box lot, take the item leave the rest. Discuss with auctioneer before you hire get it in writing about disposal but remember his time is your money. If it is at your house then you may have a problem. If the auction is at his facility then HE has a problem and your stuff is isolated. Isolation at your house should be behind a locked door
Again I recommend you go to an auction at his facility before you hire the auctioneer.