I won’t lie. In my opinion the chances of success are slim to none. But this is the best time of your life to take a chance. The more adult you get the less able you are to take huge chances. So as long as you hang on to enough money to get yourself home should things go bad I don’t see a down side (where as if you don't you could end up regretting it for the rest of your life)
That said, two pieces of advice....
First, get this book: http://www.amazon.com/Ask-Moon-Get-Percy-Ross/dp/0722529465/...
Percy Ross went from nothing to being a millionare and he attributes most of that to getting help from the right people. In that book he gives his 10 rules on how to ask for people's help and get it. The most important thing to remember if you do this is that 90% of the people in the bay area tech scene have been where you are (aka chasing a dream). If you need help and you ask right I suspect most will do what they can to help you succeed.
Second, look into hostels: http://www.hostels.com/us.ca.sf.html
Hostels are basically cheap dorms for anyone to stay in. They’re not very popular in the U.S. but in Europe there are tons of them and they serve young people with little money very well. The bay area has more than just about any U.S. city so you should be able to find a cheap place to sleep (and most have free wifi)
Anyway, hope it helps.
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