re: (First post) Housing related, what would you do?

Sounds like a festive way to get into home ownership. Why might they think the lot is divided there? What purchase of land did the trailer owner make to lead him to believe he owns most of your prospective lot? How many guns will he unload on you when you try to remove him from the land or sell it to him?

I’d tread lightly with this unless you get a quick, clear, and reasonable solution with no drama attached.