(copied from Mike Murphy's campfire chat "Money Saving Tips)
"Your farrier or equine dentist will usually be willing to reduce fees if s/he can see more than one horse at a visit. See if you have friends that may want to participate in a group visit."
Also it helps to have your horses sprayed with fly spray,so they will not be as fidgety while the farrier is working on them!!! Do it ahead of time ,so that their not wet from the spray , and therefore gets it all over the farrier!!!
Give your farrier a heads up on how many you want shod, or trimmed and if you will provide the shoes or he needs to and if so what size and specific type you want. That way he will know ahead of time how long to expect to stay there, if you have a difficult horse which may need tranquilizer, and his job will go quicker.
here is one more... Clean your horses feet daily, if not possible clean as often as possible. This will get your horse used to having their feet picked up. Reward = positive reinforcement. I don't even like to raise my voice to a horse.
Let them know you appreciate them!! Even with the best of horses (and the payment) it is a very hard, physical job. If it is a new horse, warn them that you have little background information, some horses will be great for the owners but not so great for the farrier.