If it's the yahoo article, the interview was written sometimes last year. I've since moved to a 1BD apartment in Chicago.
I lived in a park in the east bay, not in SF. Just search for mobile home parks or RV parks in SF. There's at least one but I don't remember the name. Don't confuse this with camping grounds---those are intended for tourists.
Alternatively, there are a bunch of them in Hayward next to BART, also in Oakland. The Hayward ones are pretty expensive though, like $600. We paid $495 for our spot.