Prior to moving full time to our farm, I parked the tractor in an unlocked barn an placed an 86 Jimmy blocking the only access door. Not a perfect fix but the only one that I had at the time. If you have some concealment on the property, I'd park it there or tarp it to add some concealment from prying eyes. Insurance, nosy neighbors, periodic safety checks and if you insist as others have mentioned, there are outfits who will sell you a GPS and send the location data directly to your cell phone. I've seen the latter, it's slick and fairly inexpensive. The biggest $$ hit is the cell phone monthly charge.