So, you have a single lot with three structures? A main house, and two smaller dwelling units? And everyone parks in the same parking area on the lot? And there's a gate that keeps people from wandering into the parking area off the street? And then there's a second gate from the parking area to the landlord's part of the territory? And the problem is that it's clunky to always have to get out of your car, open the gate, get in your car, drive and park, get out of your car, walk back to the gate, and close it and lock it?
And you want to know if it's illegal to have a locked residential parking lot in Los Angeles?
I'm not in Los Angeles, but if it's too tedious to manage the gate the way the rules require it to be managed, it sounds like a good opportunity to turn in your notice and find a place with more straightforward parking.
If you like where you're at, then putting up with the tedious parking routine is just the extra cost of staying where you are.
It's okay to threaten to get rid of people who don't follow the rules, even if the rule is just security-related-- like, "Keep the parking lot secure". It sounds like the ll is worried about people wandering onto the premises or parking illegally in a private lot. Are you close to shops that don't have enough parking for customers, or near a school, or near an area with a lot of vagrancy, or...?
--166.137.xxx.xx