Try this on for size.
I have a tear down house on two beach lots 2 +/- blocks to the sea.
I can if you want get you the house next door on a 3rd beach lot, and if you like the 3 story huge house on the 4th lot and a two story residence on the 5th & 6th lot possibly also two commercial retail lots for a mixed use development.
How many would you like? If you buy all of them cash, credit, or check I will gift wrap them.
I am as serious as a heart attack about this. Some have over $70K of planning, soils and engineering work and reports.
As for your question Realtors aren't really the ones to ask if you can build a four story building on a lot in the City of Santa Monica or anywhere. I can recommend several architects who deal with the City on a day to day basis. Also I would recommend a land planning attorney or land planning consulting.
While I have studied a little Landscape Architecture, I am not qualified to say yes or no as I and most Realtors do not deal daily with the planning and permitting counters of the various cities and counties in the US.
Call or e-mail me, I am about to do a post card mailer in that area of Santa Monica and might find you something by accident other than my property or anything else you have seen so far my friend.
Al Goldberg Broker
30+ years Broker
Have a great day,
Heather Paul, Realtor
"Your Local Santa Monica Real Estate Expert"