You could move?
You can move to my house, and have the obnoxious neighbors across the street...I go through the same crap. The cops have been to the house across the street many times, and they still make noise, have their parties, and have a smashed up car, washing machine, and other junk in the front of their house, and no curtains in the front window, trees growing up past the gutters.... the front of the house looks like a dump. And, we had to move across the street from them. We own our house, and can't sell- we're stuck here. I understand what you're going through, think positive, either you or the pot smokers, won't be there in a year!
One good thing about the neighbors you've described is....they don't sound very stable. People who have lots of screaming fights, people who can't keep agreements (like the once a week bad practice agreement) and people who take drugs....usually move around a lot. My guess is that you can outlive them at this address. One of these days they will move because people like this cannot sustain any sort of stability in their lives and they have too many problems to remain in one place long. My advice is to wait them out; they'll move. If they don't move fast enough to suit you, make an anonymous call the the polce when they are at their loudest and smokiest.
is contacting the owner out of the question? surely the things you described would put your neighbor's contract in default.
Well, you can ask them to fix the problems, but that is unlikely to resolve all your issues. So you've got a choice: move, or get rid of them. It might not be easy but if you're determined enough to go to war it is possible. For instance, step one could be to call the police when they are smoking pot or fighting. If they play loud music, you play it louder. Just turn it on before you leave, or set your tv/stereo on a timer. If their band plays in the ba<x>sement, upload a recording to YouTube under the title "worst band ever". Obviously these aren't nice, neighborly things to do. These are things to do when you're at your wit's end and cannot take it anymore. And I have to say, it sounds like it would take a LOT to get them to move. But if you're willing to make them miserable enough anything is possible.
I think the best option for you is to move.
put on your outfit ...so they don't have to peep through
punch em in the face
pee outside............oh weird !!!!!! sorry
When you find out let me know, I have a neighbor making a complete jack@ss of himself.