Go to the areas south of San Fransisco, especially Watsonville, or Salinas.
I was SHOCKED at the hundreds and hundreds of old RV’s lined along the road sides that people are living in because they can’t afford the incredible rents in San Jose, SFO, or Monterey Bay.
In Monterey, as long as they have a legal plate, and are moved under their own power every two days, it is LEGAL. Even if it only moves one parking space.
There’s a guy who works at and for Google, who bought a box truck, and lives in it.
http://www.businessinsider.com/google-employee-lives-in-truck-in-parking-lot-2015-10
I saw a lot of this too. I was in the South Bay Area (Mtn. View/Palo Alto) back in October.