You might want to visit, the weather has been unseasonably warm. Tell immigration that you are a tourist on vacation. Don't mention working or trying to find work.

There are hostels in SF where you can stay for cheap. Most are in the Tenderloin/Financial area. I've never seen the inside of those. I have actually stayed at one hostel, to check it out for a traveler friend. Element Hostel. It is in the same building as Medjool, quite possibly the stupidest nightclub in the city. It's a good hostel, though, and I think the only one located outside of downtown. http://www.yelp.com/biz/elements-hotel-san-francisco The mission is a bit grimy but at least its where the young do their thing.

Also I'd actually just do a vacation, the Bay Area is a nice vacation spot. Tons of stuff to do and see.