the only places with houses for $150000 are too far from San Francisco. You'd have to go due east and end up in the middle of no where.
I think the median home price in the Bay Area is around $280000
even places like santa rosa/petaluma are not too cheap because they are close to the wine country (napa).
I live in SF and work in Emeryville, which is right across the Bay, nestled against hiway 80 and bordering berkeley and oakland. There are a lot of empty lofts for sale there and prices are fairly reasonable i'm told. from there, its a ten minute drive to SF without traffic. I really like working there b/c parking is good, stuff is cheaper and you're still close to a lot.