It is only good public relations and saves unnecessary problems. This is the practice that should be used at every sale. However, most auctions provide a post-sale inspection to the buyer. This opens up the change of ownership until the point of payment. The seller is responsible to get the horse back to the stall.
Most consignors like to meet and talk to the new owners.
I think all sales are similar in these terms. If there is a misrepresentation of the horse, take care of it at the sale, right away. Don't wait until you get the horse home. But, sometimes it is a case of paying more than you wanted to. It works best if the buyer and seller get together and talk it over.