What's a good way to learn zoning rules in city of los angeles?

[Alma Mills]

I'm working on some strategies  that would require  building  multiple  Townhomes or  condos  on  a lot  what do you think the best way to find out all the rules  for  development and zoning rules?  Would a local architect know?  Must I go in to the planning department with a specific lot and plans?  What do you suggest?   Thanks in advance for your thoughts.