I bought a duplex last summer that came with tenants. The first thing I asked for were current rent rolls, apps and lease agreements. Luckily, all of their lease agreements had expired. After I purchased the place, the tenants had to fill out my application, go through my background check and then sign my month to month lease agreements.
It took several months to retrain these tenants and I am still working on it. They were used to having a nonexistent landlord and a neighbor lady next door who was supposedly managing the property, but actually caused more problems and drama then anything else. After many discussions with the tenants and neighbors, I got the place in order, but it took a lot of work and a lot of time.
Every time I got a complaint from a neighbor, I pulled the tenant out in the front yard, in front of the whole neighborhood and chewed their ass. They learned that I wasn't going to put up with any crap or drama. I made it clear that it was my house and they would abide by my rules or they would be leaving.
One other thing they learned was that if they had a problem, they could actually call or text me at any time and I would solve the problem right away. Not days or weeks later like the previous landlord. I wasn't happy about taking on someone's else tenants, but they pay on time and with a lot of patience, a big stick and a lot of shock an awe, things finally have turned around. For now!