If you go to the Laguna Beach web site, they list the parks that are "legal" and those that are off limits to hobbyists. Despite the restrictions, a pilot with a Part 107 license is exempt from those limitations.If you decide to go through with the Part 107 certification, you'll feel more confident of where to fly after passing the test. Generally, if you are outside the boundaries of airports, you're safe. If the area is posted no RC Models, you're not. Very few So. Calif cities have no fly ordinances, but Laguna Beach does, however you can still fly in certain areas in Laguna Beach, like Top of the World. Whether you're in a legal area or not, I always fly as stealth as possible, away from people that can be a nuisance. Hide and launch.
I also avoid people as much as possible and there are days I can find local parks with zero people.