I don't know what you're talking about. Renting here is insanely expensive. I pay $1500 for a tiny room in the tenderloin, subletting from a friend who is paying $2900 for the place. It's a small two bedroom with no common space; just two rooms, a small kitchen and a small full bath. Studios in this neighborhood start around $2200.

When I live in São Paulo, Brazil (which isn't exactly cheap and going out can be as expensive if not more expensive than San Francisco), my dad and I split the rent on a 2700 ft^2 penthouse duplex with 4 bedrooms, 3.5 baths, deck with barbecue pit, dining room, living room, family room. It was one block from Avenida Paulista on Alemeda Campinas. We each paid around $1300 to cover rent and the building fees.

San Francisco is stupidly expensive. The landlord trolls sue to block every single possible development that could alleviate the housing problems because it allows them to earn increasingly more from their real estate with little to no additional capital investment.