Hey there,
My comments are not regarding either school, Silicon Valley or San Jose in general. Folks arguing about SF vs. SJ gets tedious. Personally, SJ is too much like Phoenix,Az, where I spent my first 19 years for me to want to live there.
This is in regards to you choosing SFSU (And thus, SF as a city...)
TRANSIT
Several folks are right in that you could live in Berkeley,Oakland,Daly City or another surrounding city and commute to SFSU. Whoever said that SF doesn't have a good public transit system should take a better look at the Easy Bay (Berkeley,Oakland), or try where I grew up, which had buses until 9PM...and Phx has a whole lot of walking room...
Buses are only 50 cents with a student ID, cheaper if you get a monthly pass, which also covers underground lines. The 'M' line goes from SFSU to downtown in about a half an hour, even at rush hour, since it is mostly underground. BART (Monorail) connects you to 90% of the other cities that you might want to visit (Or live in, and commute from for school...), and the rates aren't that bad, with a trip to Berkeley coming in under 3 bucks, around 5 bucks round trip.
As well, there are many 'Owl' lines, 24 hour ones, and it is possible to get nearly everywhere with a little planning. Likewise, the City is only 7 x 7 miles, so walking isn't a big deal either.
We have a lot of cabs, which I myself use, since I am often running to work 'almost' late, or coming home at 4am with a pocket full of tips, and catching a bus downtown at 4am with lots of cash is not a smart idea.
Look on craigslist.org under housing for an idea of apartment costs. I pay way too much myself (1447), but I get to live alone in a 3 room apartment, and it is worth it to me.
BILLS
My bills in a nutshell:
Cable-Kickass HBO/Showtime package + Cable for my net, about a hundred a month.
Power, about 100 a month, give or take. I just removed my metal Halides, so I expect (Hope for) a drop.
Phone is 60 or so, very basis.
Food isn't really that much more, you can still get a 5 dollar super burrito, or 3.50 lunch specials in chinese places, and there is a great selection to try.
JOBS
Yes, you can do fast food or what not for min wage, or you could do what a whole lot of students do, find a cafe. SF is a city that runs on neighborhood cafes, coffee shops, etc... people here are quite good tippers, compared to elsewhere, so that 8.82 becomes 13-15+ fairly easily. I wrok in a Nightclub (You would have to be 21+), and, while I don't want to post my earnings, take another look at my bills etc above, I am doing fine.
plus, there are a lot of great reefers here, as well as in SJ etc, to trade with, so your hobby will get an easy boost from trades, freebies, etc...
Give the bay Area a chance, it is a pretty rocking place to live.
I have to run off to do some laundry, but if you have any more questions, feel free to ask.
-Ron