Hey! I recently started leasing my DREAM facility (november 1st) .. I would MOST DEFNITLY charge any instructors coming to teach my boarders. I have to much to lose! The previous person that leased the barn got underminded by another trainer and ended up being the assistant manager of the barn SHE was leasing! And that is certainly NOT going to happen to me. I put in all my boarding contracts that if someone wants to ride with another trainer it has to be first approved by me and I will charge a $25 ring fee per lesson. If there is over 3 lessons it will go down to $20 per lesson. They also must ask me everytime this trainer comes to teach. All of the boarders I have now ride with me anyways and don't seem to have any desire to ride with anyone else. I also try to host one clinic per month with a notable trainer. Mostly grand prix dressage trainers or trainer who are VERY good in my opinion. Most of these trainers are relatively expensive so I have no worries about any of my students leaving me for them. I ride with most of them anyways so they are basically getting most of the same info from me for a cheaper price! Anyways... hope this helps a little.. I guess you have to ask yourself how important your facility is to you.. that is if you don't own the place! Atleast that's how I see it, you never know what people are capable of!