What I discovered, and my nightmare "neighbors" proved this, is that generally when certain behavior, like bullying, harassment, bad language, threats, etc., AND the neighbor has no respectability the problem will take time to stop, even if the best practices are used. (like contacting and reporting to Crimestoppers/police and if they are renting the property owner each time).

If the neighbor has any respectability, and the vast majority of people do, then all it takes is generally one police call and report to stop it.

This is why I indicated in another post that knowing the history of the problem neighbor can be very helpful. People who cause trouble to you usually have caused trouble to someone else.