Be nice and let them settle in.
And if they still take the Michael then allow yourself to absolutely lose your shit with them.
We had issues with neighbours when we lived in our flat. We were really nice to him and so was he to us but he kept pushing it.
Parties, prostitutes (he was married, working down here for work, we heard him making love), coming home drunk really late and putting tv on full blast to fall asleep. This was every night.
Our bedroom was next to his lounge. He made love in the lounge ... unless it was porn he was watching? She sounded like she was loving it.
One night my partner went round during a party (I was heavily pregnant) and really kindly asked them to turn it down. My partner is a reasonable and non confrontational human being. The guy slammed the door in my partners face.
I on the other hand was raised by what I can only describe as a pack of wolves.
One night the neighbour came home blind drunk and switched on the tv and fell asleep. It was around 3am .
I got up, walked into the corridor , slammed the hell out of his walls on the outside, banged on his door, kicked it and screamed. He woke up in a daze and opened the door and said ‘what’s with the racket?, you woke me up’
at which point I just launched a foul mouthed tirade about his parties and his prostitutes. Called him everything under the sun. He screamed back at me and told me women shouldn’t speak to people like that and that I’m no lady. 
I scoffed with a scream and continued to say whatever came to my head. I was beyond reasoning with. He slammed the door in my face.
I continued to bang on his walls as I walked back to my apartment . And then went back to bed. My partner told me this will only make things worse.
The neighbour had switched the tv off and we were able to go to sleep. we didn’t hear a peak from him after that . we moved out a few months later.
In hindsight as a heavily pregnant woman at the time I shouldn’t have put myself in that position. However I’m assuming the months of lack of sleep from the prick just got the better of me.
I actually don’t lose my temper and look like I wouldn’t hurt a fly. But desperate times ...