First off, Racist.
Second, depending on where you're at in the bay area, the crawl space can be like 2 feet high underneath a home or much larger because of all the natural hills. My home is a bit on a slope, so the they built a much larger crawl space to make sure the home had the necessary height. For example you can enter my back yard on the top side of my home which puts you level with the top floor of the home, or you can enter the back yard on the bottom side, which is level to the bottom floor (2 story home).
Right now our place is listed as 1820 square feet (3b/2ba). We're adding another bedroom and bath, with an extra 500 sq ft.
So value-wise, we're going to be getting a massive jump after this remodel is done. Probably will increase value of the home by nearly 30%.