You might have some luck checking the sublet or roommate listings on Craig s List. You can search by neighborhood.http://www.craigslist.org
You can often find a good cabin / condo that is available for a cheap price for an extended period of time. There are many places to stay around the San Fran. area.Rather than give you a specific property name and location, I would suggest that you do some research on the available houses/condos, the prices and the locations. I have used justvr.com in the past and it was quite helpful for narrowing down my choices and booking the stay.