Given the location and the shape of the house, I am almost certain the boat is a Stephens. It could have been built at any time between the late 20s and the start of WWII. However, the vertical front face on the main cabin suggests late 20s. By the 30s the forward cabin house faces were starting to become raked aft. The picture below is a 1936 Nunes Brothers built in Sausalito, CA.