I agree wholeheartedly with Patrick. Mystery shopping is a job and you have to do it well but it is also a lot of fun. You get to meet new people, role play AND you get paid for it. Read your instructions, don't take on too much at the beginning and find the shops that you really like. Get good at them and continually add to the list. Once you are comfortable, start planning routes, small at the beginning, 3 or 4 at a time. Before you know it, you'll be doing it full time! Get a good route planning app - there are several free ones and develop good relationships with your schedulers. If they ask you for a last minute job or one a little further away than you'd like, do it if you can - they will remember you. I wish you all the best and feel free to ask any questions. This is a friendly and helpful forum.
I lived in SoCal for about 20 years before relocating to Texas. I still have a lot of friends out there. The nice thing about your area is that it is so congested! Really! There are a lot of varied opportunities out there. I'm in a semi-urban area with a lot of distance between some of the shops. I'm sure glad my car gets good mileage.
Have fun with the shopping out there.