There have been recent buildings advertised in SF with units as small as just over 200 aq ft - a futon and a microwave with a roomette bathroom, I think. And for those they want over $2K/mo rent. I like my place just east of Sacramento with <<$1K/mo mortgage payments all up, paid off in <10 years.

From the angle of the pictures, that place must be on the edge of China Basin or the north edge of Mission Bay. They should issue seat belts - it'll really get bouncy there in the next earthquake (liquifying ground).