We lived in an area where the yards were postage-stamp-tiny. Our house was brand new when we bought it, in a neighborhood in the middle of gentrification, I guess, but then the bubble burst (hooray for 2008/2009!!) and all updating came to a screeching halt. So while our house and its siblings were brand new, we were right next to a bunch of rentals and very small places with waaaaay too many people living in them. It was tarp-covered roofs, barking dogs and weed-choked lots all around.
Neighbor house #1: We'd been living there maybe 2-3 years when a very large family moved into a tiny mobile home next to us. The lot was literally ~4000 sq. ft., but with a house on it, so the little mobile home (600 sq. ft. on a good day) was literally 20 ft. from our house and our bedroom window looked directly down into their tiny backyard.
The people in the mobile home threw a party. Cool. I got no problems with that. They invited a band, who set up speaker stands. Their "audience" was literally 10 feet away from them. But they needed speakers. Except.... the band included BRASS INSTRUMENTS. Like, a tuba. Pointed at my house. And amplified. We allowed it until, like 9pm, then asked them to turn it down. They didn't. So we called the cops, who asked them to turn it down. They did turn it down for a while, but as the night went on and the beer flowed, we could slowly hear the instruments coming back out. First the flute, then the trumpet, then the trombone at ~2am. That was a looooooong night. They never threw another party like that, but when we tried to sell the place, the outdoor room they'd built using nothing but tarps did cause us problems with convincing buyers that the neighborhood really was pretty safe.
Neighbor house #2: The house itself was a very similar setup to the first one - relatively normal size house on a tiny lot, but this one had a 2-car detached garage with a tiny apartment on top. One of the garages downstairs was "owned" by the house, the other was for the apartment. A year or so after we moved in, the place burned, which was sad, but no one was hurt and the fire was contained and stuff, so the owners rebuilt the apartment and rented it. Cool. New neighbors! And then...
Our first inkling that something wasn't right was when we walked past the house and their garage was open. Instead of parking a car in it, they'd turned it into their downstairs living room. Which... okay. Fine. But they'd also turned their friends loose on it with black spray paint. And taken a hammer to the brand new walls. And stuff. Sucks for the owners, and also does terrible things for our property value. They'd hang out there in the evenings, generally being loud and obnoxious. And, oh, the pot smoke. So much.
ss
Then. They threw a party. Invited, like, 50 of their closest friends. Which is cool, but the apartment was maybe 800 sq. ft., so of course the party spilled out into their garage/room and into the street, where they decided to start racing their motorcycles at 11:00 at night. Cops were called. Many arrests were made (this was back before pot was legalized in our area). Quiet was finally restored.
I was so glad when we finally moved.