Sunnyvale is like 42 miles South of SF. You're pretty much in the Southbay area at that point. So unless you don't mind driving 45-1hr to get to SF, then that might work..


Map

Otherwise, like everyone else has been saying, I'd look into South San Francisco, San Bruno, San Mateo as they are outside of SF so they're cheaper, but not that far away from SF. Anything south of Mountain View is already going beyond the halfway point between the South Bay and SF. Mountain View/Palo Alto is about the midway ish point (20 miles north of San Jose and about 30 miles south of SF).