I’m going through the same thing… Just started a small extension on the back of the house before the new neighbours arrived. She is 21 and addy bought her the house as a birthday present! We went round and said hello, explained the parking situation and we have two small children, but it seems to have been in vain. She like her music loud, smokes outside and generally acts like a diva. The neighbour on the other end (a policeman) doesn’t seem concerned which kind of leaves us in the unenviable position of being the bogeymen nextdoor.
We almost considered knocking the extension down. What should be a nice moment for us is being ruined by the cosntant thought of “are we doing the right thing?”.
We are keeping a noise diary., but want to avoid the council thing.. please let it stop!