I'm surprised that no one has posted about this yet! As a horse owner, YOU need to accept a little responsibility for attending to your horse when the vet or farrier comes. It's a good idea to be there when the farrier comes, and learn how to handle your horse in order to make it as easy on the farrier as possible. I know a farrier who charges extra for a horse that is dificult to handle, and 2 more who will not touch difficult horses UNLESS the owner is there to see and (hopefully) work to correct the misbehavior.
It's also important to be with your horse when the vet comes. In addition to being there to handle your horse, you'll also get the diagnosis and treatment protocol first hand, rather than passed down from the BO or barn staff.