The HDL notes say "Figueroa 5th to 6th". I posted this picture a couple of months ago, and I believe the building on the right (under the TWA advert) is the one behind the little house.
USC Digital Library
Here are a couple of aerials. The Richfield Building is roughly in the center near the bottom. I've arrowed where I think the little house was.
1948
Historic Aerials
1952
Historic Aerials
This is another HDL picture from 1957 (previously posted by
FredH).
Huntington Digital Library
The white building with columns is the Bur Mar Hotel, so, using the 1956 CD (below), the dark wooden building next to it must be the St Dunston Apartments. If these apartments are the ones on the left of
Tetsu's picture, then could the little house have belonged to Ray F Allman?
LAPL