Do you know where this is?
It is Windsor Terrace, a little area of big houses on 8th Ave and the east side of 9th Avenue between Lawton and Moraga.
This is looking up 8th Ave:
Here's a link to the only historical photo I found (coincidentally a person was asking about this topic on the Western Neighborhood Project site). It is the same spot and dated 1914, you can see a shadow of the brick "gate" at the bottom left.
I always admired this enormous house at 8th and Lawton.
I haven't been able to find any further information about the development.