Seems that you need R5 zoning. Find a place and start working with the City Hall (Dept. of Building and Safety) officials. Get in the line to get permits, because it could take up to 6 months to get what you need. You would be working with a city inspector who will be overseeing the project if you want to make additions. The process is not easy and many people get frustrated. But it’s possible.

It has to be Zoned as Commercial if you intend on a business there. It can be Residential-Commercial, but its just like a Church, or a School, they are zoned Commercial, some are Commercal-Residential.
Then you need a Business License,Tax ID.
After that, your pretty much set up.