We have room phones in our hotels, so if someone gets loud, there have been a few times where I called the person above or to the side of me and just bitched them out while changing my accent. Since there are people either above or below us, and then on both sides of us, they never really know. Or no one has come and told me anything. It stopped after that.
Until the girls next door really enjoyed laughing and talking in their bathroom loudly when it was past midnight on a school day. They would move furniture around, drop things as a hobby, etc. Finally, I had enough and so for a week straight, I would call that room in the middle of the night, let it ring a few times and hang up. It was before exams, so staying up until 3 or getting up around 5 wasn't unexpected.