Hi Violet71,
The first place I would start your research is post #1 here which has all the basic information, steps, and guidelines you will need along with links to some of the most helpful forum posts.
Once you get to step #3 … the list of some of the better options and possibilities in the Los Angeles area I’m aware of is in post #2 here. The first post I linked also includes links to some of the better online manufacturers and retailers I’m aware of.
Local testing is always an important step IMO so that you have a reference point that can help with an online purchase if that’s the direction you decide to go. There are some good options available in Los Angeles that you can test in person and then you can compare the “best” local options with the options you have available online.
Phoenix