Any tips for living cheaply in SF?
thesethings: I would really try to get a little bit of additional income, your numbers are very tight. Plus, you don't want to move to another city to stay in your room the whole time because you're broke, you want to enjoy your time in SF. $700/room is doable but still quite rare (especially without strange catches, like "3 bus rides away from X.")  I'd put a bunch of energy into finding the room before you take off, maybe check out AirBNB? Have a separate post about housing hookup?