If you are old enough - Get a legal lease agreement with your uncle. That will give you the right to prosecute the trespassers.
You will want photos of them doing their thing and more. A trail camera in a tree pointing down at their parking spot should do it.
Do they bother you by making a point to come over and harass you? Sounds like they are giving it their best shot.
You need to get the LAW involved and repute these losers every time they do something unbecoming. You can talk to your local game warden and maybe the local sheriff - in person. Tell them the story and ask them the best way to proceed so that they can help you. You need to worry about retaliation if you do have them arrested.
I was threatened by several guys at one point - my dad was in a tree less than 100 yards away, watching - think that kept the other guys civil. I called the local GW and he asked me to be bait, that these fellows had been causing problems for years. I told him that he could use an undercover agent since I'm not up to getting beaten or shot over a hunting spot.
Last story - I also bought land to hunt years ago....could not keep the locals off even after calling the cops. The sheriff lived across the street from the dirtbags. They shot whatever they saw, legal or not. I had to stop going because I was starting to think of how to hide the bodies. 3 years, $3,000 worth of food plots, fencing, no trespass signs, etc. I never saw a deer during the season but found my pet deer laying dead on a trail one day.... Sold the land to a builder.
It is a crying shame that people are so bold when doing illegal deeds. Get the law involved - 1 warning, 2nd time press charges. Then if someone else does something, press charges again, and again. You need everything documented in case they do something to your car, stand, etc.