If you can do it, please post the details, as I'll be very impressed! If you want to live in an actual structure (as opposed to a vehicle), you may need to be open to sharing a bedroom. One thing that did occur to me is a roommate who travels a lot--perhaps someone who works for an airline and is based out of the Oakland airport, or someone who is often gone/traveling during the week?
Another possibility is some sort of caretaking/maintenance for rent arrangement, but that may not be compatible with your desire to get up and go (if the caretaking involves a person as well as a property).
Or, if you can find a multi-person place and set yourself up as the master tenant, you can perhaps shift some of the rent off to roommates in exchange for handling communication with landlord.
Final suggestion is to be more flexible than average in your definition of what is "close" to public transit, if proximity to transit will be important for things like getting to work. For example, that map linked above looks at rents within a half mile of a BART station. The weather is really nice and mild here something like 350 days of the year, so if you're in good health there is no reason why you can't live a mile or more from transit. We've always lived about a mile from major transit and find it seems to be a nice sweet spot in terms of still providing good access for daily commuting, but also resulting in a noticeable decrease in rent (for example, that map above shows a 1-br rent "near" my BART stop going for about $250/month more than what my husband and I currently pay for a 2-br a mile away).