My parents' neighbor was literally stalking my mom for a while, calling the police on her for things she did (that are perfectly reasonable and within the law) while she was out and about town, and started vandalizing their landscaping by cutting everything at night. That's not all, but those are the highlights. No clue why he was such a douchebag, but my dad thinks it's because he declined to buy insurance from him even though "EVERYONE gets their insurance through [him]."
I have a rental next door so it's been a revolving door over the past 11 years. Some good some bad. Right now good as while they really don't have a lot of money, they do have integrity. They so their best to mow the grass, keep the place clean and neat, they are reasonably quite and peaceful. Plus they have 3 kids. So it's nice to hear the laughter, shreeking and giggling while they play outside.