New landlord problems, tenant that thinks they're in charge

[Matthew Anderson]

Just bought my first property in Pittsfield, New Hampshire, it's a four-unit built in 1850 my family and I plan to do an owner occupied unit with tenants in the other 3 units. The previous landlord seemed to have forgotten about the place. There's a lot of deferred maintenance and my favorite thing was the inherited tenant. Upon meeting him he talked a lot about how long things took to get repaired and how the current owner/landlord was unreachable. He then went on about all of his future plans and how fire department/ town enforcement and landlord will do nothing. He even stated that what they don't see won't kill them and he has made/ currently making upgrades in his own unit. He was very open about his plans to expand his porch, and remove all the trees on the property to expand the parking lot, mind you both these things require permits to do. With all that being said, he is on the other landlords lease for a while longer, he is a yearly contract. Any ideas of how to handle that kind of tenant?