I lived in two of these in Madison, WI. I'm not sure if was legal, but my landlord rented each bedroom in half a house individually. Four men, one bathroom, beer cans in the shower (Why?), but the bedrooms all locked individually and we weren't mutually responsible for each others' rent.

Second one was a former HoJo parked while awaiting condo conversion. Imagine a hotel room stripped of all furniture, with a single kitchen per floor. Had to wash my dishes in the bathtub, but otherwise it worked for me.