They're quite normal. I once asked the neighbour of I could climb over the fence via her balcony to mine 9 high, cause I forgot my key, so I guess I'm the weird neighbour. The guy from downstairs very often forgets his key and then he rings my door bell to open the door from upstairs. First time he did that I was like: Who's that? A homeless guy trying to break in? Oh it's the guy from downstairs. Come on in.