San Fransisco in general like in Craigslist and not AirBnB has plenty of listings of apartments where a dining room + living room where they added a flimsy partition to separate the two and advertise as a bedroom. I guess no one complains tho since you just choose not to rent since renting long term is usually a look before signing proposition where as AirBnB you pay before you go and it needs to be correct site unseen