I had trouble in my neighborhood with people either letting their dogs run free or even walking them to the side of my house to take a crap. I set up a CCTV and when I see the owners I go out and accost them and tell them how much we hate their dog crap outside our house. If it is running loose, we check the dog on CCTV and scrape it up and throw it in the owners driveway. It has taken a long time (years) but it is pretty much taken care of. No one walks their dog by our house and the loose dogs don't seem to be loose any more.