We lived in a 2-bed, semi detached house when our 2 DC were little, and we had a lovely couple living next to us - 10 years younger, so they were mid 20s and we were mid 30s at this point. We lived in harmony for 6 years, and they said they never heard our DC - they were in the bedroom not attached to next door thankfully!
We hardly heard each other at all... We socialised together, went for meals at each others homes, and had barbecues together in the summer. It was a wonderful neighbour-friendship.
Then when our DC were about 6-7, this couple moved as they wanted to be closer to family.
A couple in their early 50s moved in, and they were fucking vile. They had bought their house on right to buy on the big sink estate 2 miles away, and sold it and made about £40K (and 22-23 years ago that was a lot of money!) Then they added a £20K mortgage to it and bought the semi detached house attached to us.
From the first day in, they played loud thumping music, and had between 4 and 8 people visiting at any one time, and thery were loud and obnoxious. They played music til 1am and 2am most nights, and DH and I (and our 2 DC in the bedroom not joined onto them) could hear the thumping drivel coming through the wall. None of us could sleep.
After a few weeks, I knocked on their door at 10pm after tolerating thump thump thump coming through the wall. No-one answered. Long story short, it turned out they were out that night and had left the radio on to deter burglars!
Midnight they came in. I went around and knocked the door again, and she shouted down from the master bedroom 'who the fuck is that at midnight?!' I said 'it's me from next door, can you turn your music down please? It's been going since 7pm, we haven't been able to watch TV all night. And our kids can't sleep!' She said 'it's my fucking house and I'll play my music as loud as I fucking want to.' And then she turned it up louder. We called the police but they said it was a civil matter and we need to contact the council.
About 3-4 months after they moved in. and them blasting music out and having parties with pot smoking and loud thumping music and people pissing in our garden, we could stand it no longer. We bought a new (4 bed) house, and ours went to the homebuilders as part-exchange. (We still had to stay another 2 months though, as it didn't all go trhough overnight.. ) A private landlord bought our 2 bed house, and private let tenants started living there. I hope these old neighbours of ours got dreadful neighbours!
I cried so many tears at having to leave our lovely home because of these vile cunts.... I hope they rot in hell.
p.s. Once we had moved, I became happy in the new house quite quicky. (Fortunately!) 
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