Noisy neighbors can make your life a living hell. I used to live next door to a jerk who not only played his stereo astoundingly loud all night, but would actually turn it up louder after you banged on his door and asked that the volume be turned down. (This is the same guy who shot a gun through our wall as described in the writeup to University Townhouse Apartments.) After a while, you get to the point where you don't even bother asking them to turn it down, you just call the police.