Maybe lining up a room before you leave might be a slightly better plan, unless you have a large bankroll and can pay for a decent hotel for up to a month while you look for a room for rent. As far as the three cities you mentioned above, Finding a nice part of town in Oakland and San Jose can be a little tricky, I would advise moving to Santa Rosa since I have lived there, the only downside is the job market there sucks so you will most likely have to commute to a good job.
If you are planning on renting a room and growing that may take some additional searching to find a good place to do both. Seems like you kinda didnt plan this out too well, I wish you the best of luck in your adventure.