I understand I guess. Its not buyers that haul them. You do it on your own or hire out your own. And while it is best to have them preconditioned, they don't have to be and quite a few are not. Its a simple process, take them to the stockyards or OKC West, tell them what you have and what you done if anything. If they are fresh off the cow, tell them so. They will take them from there and sort them in whatever size groups that is needed to get you the best sales price. The stockyards uses commission companies, OKC West does it all in house.
Both pen them in their own pen with fresh water and good feed. Commission is by the head and runs about $20 to $27 per head, feed included. Pricing is usually about .10 to .15 a lb better than my local barns and your shrink will be 0 to 5% depending on how well they are eating versus 5 to 12% at your local barn.
For me the higher price easily pays the freight with the shrink difference,making it worth it. Commission is a few dollars a head cheaper depending on how early you take them before the sale.
Probably not enough $ for you to make a difference, but it is to me plus I have some pride in putting a good animal into the market that I feel the buyer will be happy with. To each his own I guess.