<The Bay Area has been really bad about building> This is largely due to politics. If you were a speculator considering building a rental apartment building,

<The Bay Area has been really bad about building> This is largely due to politics. If you were a speculator considering building a rental apartment building, you face: 1) Rent control. (Those cities and counties that don't have it are all considering it.) 2) Requirements that you allocate a percentage of your units as limited to "low income housing", with those units becoming permanently constrained 3) permit costs, neighborhood opposition, and other city-specific barriers 4) high material prices and construction costs (e.g. earthquake and flood codes) 5) high labor costs