Update on the Joe Homeless front: our neighbor who owns the property (and trailer) came last night and moved Joe Homeless and his special lady friend on out. She called and apologized profusely to Shaun, then came to the door and apologized in person to me. It's hard, because this woman has been kind to us all 6 years we've lived here, but was clearly making really bad choices by hiring alcoholic homeless folks and allowing them to live in our driveway. She promised to move the trailer to another location, to avoid leading the alcoholic homeless folks into temptation, and promised to help us with anything we needed.
So, a tentative resolution to our sticky wicket. Thank you for all the impassioned commenters, too, hey. I had no idea so many of you would offer advice! I should ask for input more often, I guess.
The moral of our story is, um, don't let alcoholic homeless folks push you around. I think.