I have built an equipment corral out of large boulders that I have dug up in the yard and existing trees. Unlike a traditional fence boulders are much harder to defeat without heavy equipment. You cant cut a boulder with a battery powered grinder.
Whenever I leave the property I block the corral with a vehicle and disable it so that it cant be moved easily. In addition to motion sensor lights I have video cameras set up to keep an eye on things. Anything that slows them down or exposes them especially video is a good deterrent. An old trick I use to use was to gut the cigarette lighter and use it to complete the ground side of the starter solenoid or relay. If you left the lighter popped out the car would not start if you needed you could take the "lighter" with you and no one would notice it missing, however, the car would not start.
Another good deterrent is to elevate what you don't want stolen. Putting equipment up on pallet shelving, you cant drag it away or into a truck without first getting it off a shelf. Way too much work for the average thief. They would have to get your lifting equipment started and then get the equipment loaded on their truck. If they go through that much effort you were going to loose no matter what.