I was fascinated by that photo of the El Patio Auto Laundry (what a great name!) and went searching for more info. I stumbled across this group of additional photos.
[source: jalopyjournal.com]
Also came across these early-1930s photos of Royal Coach Auto Body Works on Santa Monica Blvd. I assume the man in the white coat is the proprietor.
[source: jalopyjournal.com]
[source: jalopyjournal.com]
[source: jalopyjournal.com]