It is a famous old saying, sometimes true, sometimes not. A common source of legal conflict is the building of fences, issues often come up about where the exact boundary line is and what the local rules are for building fences. To avoid winding up in court before you build a fence, it is always a good idea to know where your boundary line is; build on your side of the boundary, talk to your neighbor, keep them informed, and follow any city or local rules about the location and height of fences. Not building your fence without proper planning can get you into a hot legal battle with your neighbor; never a place you want to be.
Ed