The State Department of Agriculture requires a barn or stable that boards horses for any reason to have a license. If you are not boarding horses for any reason and the horses are as you say your own private horses, you do not have to have a license. As far as preventing liability situations post "No Trespassing" signs. The second thing to do is to post a sign that pertains to the "Equine Immunity Act." The signs can be purchased from the Georgia Horse Council (www.georgiahorsecouncil.com). The sign reads "Warning: Under Georgia Law, an Equine Activity Sponsor or equine Professional is not liable for an injury to or death of a participant in equine activities, pursuant to chapter 12 title 4 of the official code of Georgia annotated." Information on who needs a license and how to obtain one can be obtained from the Georgia Department of Agriculture (www.agr.state.ga.us). Of course anything you can do to discourage people from entering your horses' facilities such as locked gates, etc., will help.