GET A DOG! I would get a German Shepherd! I had one and they are very protective of their property. Other than the incident in June, seems like the guy travels past your place around the 3rd week of the month - 20th, then the 18th.... not sure if there's a pattern or not, but I think I would put some more items out for the guy and take a vacation and lie in wait for the guy and make a citizen's arrest at gun point if the police aren't willing to step up.

Good luck. Looks like one of those folks you see in the Walmart pictures.

Mac