Guests refuse to leave Airbnb host's house

Yeah, these kinds of things are somewhat well known among people who do vacation rental, but many AirBnB people are new to it. It's not strictly AirBnB's responsibility to help out, but maybe they could provide some pointers to common pitfalls. Almost all jurisdictions have some way of distinguishing "vacation rental" or "transient accommodation" from "long-term rental" and the difference is often important (30 days is a common cutoff). Also, if a rental is explicitly fixed-term and both sides agree to that, it's usually better to get that agreement in a written contract.

Also doing things like cutting off power/water/whatever is rarely a good idea. Just get the person legally evicted, don't harass them. That'd even be true if it were transient accommodation: if you refuse to leave your hotel room, the hotel will just call the cops and get you officially booted for trespassing, not resort to roundabout methods to smoke you out.

According to another article, http://www.sfgate.com/realestate/article/Squatters-don-t-sit... , it is suspected that the squatter is intentionally running the AC full blast with the windows open.