Wow,
SillyMe, sounds like you must live in my spare room! We've lived in our apartment for 3.5 years. When we moved in we had the sweetest old lady upstairs who would invite us over for tea and cookies. Well, she got lonely and moved to be closer to her kids.
Then a 20 something guy and what I assumed to be his sister moved in. They worked night shift so they would be showering/moving furniture/using the blender at 2am! Then one night I hear some noises coming from upstairs which made me hope and pray that they weren't siblings.
Well, they finally moved out and a whole family moved in upstairs! There was a mom, dad, 2 kids about 6 & 10 and a whole bunch of other people would stay there too. Well, the parents wouldnt' give the kids a key so they'd stand outside the apartment for their parent's to come let them in. The family didn't speak a word of english so when their toilet overflowed and flooded MY bathroom, I went and banged on their door trying to get them to turn off the water to their toilet, well that was frustrating. The dad would smoke (the smoke would waft into our windows) on the balcony and flick his cigarette butts onto the ground or onto our balcony and I'd say "excuse me, i think you dropped something", he'd shrug like he didn't understand me.
When they finally moved out I was thinking, great, a whole rock band is going to move in upstairs. They'll practice when i'm sleeping and they'll probably be

and have cages upon cages of snakes and scorpions and spiders who like to escape. That's how the trend seemed to be going anyway. I'm happy to report that the new guy upstairs is fairly normal, no drums or creepy crawlies as far as i've seen. I barely hear the guy it's great!
We used to have the most fantastic across the hall neighbor. He was friendly and clean and quiet. Then he moved out. An old couple moved into his apartment. The lady smokes, no word of a lie, 3 or 4 packs of cigarettes a day! I'll leave for work at 7 and there will be 7 or 8 butts in her balcony ashtray and when i get home from work the asktray will be heaping (and smouldering) and there will be 3 or 4 empty packs beside it! Then in he evening when I take the dog outside she's sitting there riffling through the disgusting mess looking for butts to re-smoke. EWWW! Now she's taken to smoking in her suite as well as on her balcony so the smell is permeating into our suite as well. I can't even open my window cause if she smokes outside it come right into our window. I've complained to the resident manager and they won't do anything about it.
I can't wait until our house is built. Good news is that they're framing it right now!