I wouldn't list my occupation as mystery shopper. It might cause problems, such as too much curiosity, and it might also get out. Merchandising or marketing are better terms for me. I think my husband put my job title as worker on our last tax return. He thinks we were audited three times by the IRS specifically because we looked suspicious as self-employed people.
I haven't had your child care situation, cyberjf, but I have been in your situation financially so I'll comment on that. In order to use a public health clinic, you have to register ahead of time (before you or your family is sick). They pre-qualify you financially. Some of the clinics also have dentists. I don't know if any have nurse-administered pharmacies. Ours used to. I wouldn't recommend government health care to anyone except someone who has to use it. It is very, very frustrating to be a patient at one. When I tried to pre-qualify, I didn't have a current tax form handy so I walked in with a bunch of check stubs. I told them I also got bank and PayPal deposits. Their eyes glazed over. I suspect their eyes will glaze over with any kind of spreadsheet, too. They are used to dealing with people who didn't finish high school and have "traditional" income. Anyway, they absolutely refused to consider any income that wasn't on a check. They wanted to know how often I got the payments. I told them that a certain number of merchandising companies considered me an employee but the pay wasn't the same each pay period, and that the others were sporadic. Their eyes really glazed over. Anyway, they came up with an amount that was pleasing to them. (The new person doing that job there probably has a better grasp on dealing with other people's finances than the one I had to deal with.) By the way, when I got priced out of the discounted medicine system after the tax form of a few years later showed I made too much, they forgot to tell me I was paying full price until I owed several hundred dollars. I thought I owed less than a hundred.
Public health clinics have a WIC (Women-Infants-Children) program, too. If you are on prescription medicines, the public health center can advise you on how to get free medicines from the pharmaceutical manufacturer.
You probably already know about clinical trials. They are sometimes hard to qualify for, but you, not your entire family, can get free checkups and medicines, as well as usually paid mileage to and from the center. All you do in one is show up and keep a diary of your medical situation. Start to look for them in the metropolitan newspaper's display ads or call a research or teaching hospital and ask. After you have the phone numbers of several research centers, you can call them periodically or they will call you when something comes up that it appears you qualify for.
Other things you can consider are free lunches from various organizations. Schools sometimes offer summer lunches, I think for a fee. Here, a Methodist church has a free lunch on Thursdays. Some people just go there to eat to give donations for others. Also consider a program called Angel Food. You can get a large box of excellent food for as little as $25. It varies by month, but can include apples, steaks, etc. Churches have it. In my experience, they are Baptist churches. You can ask around. One local church orders extra and if they don't sell, they give them to people who can't afford the boxes. If you need something unusual, such as a wheelchair ramp, ask around to local organizations. A local Catholic church builds them for free.
Your husband has probably already filed for unemployment. In my state the rules are so byzantine that it is virtually impossible for a contract person to qualify or to feel honest about charging a specific company. Everyone knows about the resale shops, flea markets, Salvation Army, Goodwill, etc. We have a Christian Assistance Ministry (CAM) that all the churches support so they can send anyone who asks for something there for help. You might find someone, perhaps through the daycare centers, who will hand down children's clothing. If you need eyeglasses, check with the Lion's Club before you see the eye doctor. The glasses might not be fashionable but they won't be expensive, either. In this age of cell phones, do get all your friends to call you when they find sales in the local grocery stores.
Blood plasma centers pay for your "donations". If you happen to find one that is also mystery shopped, you will be paid for the shop and for the donation. They also have "special population" donations. At first, I thought that was for drug addicts or something like that. It isn't. They give you free shots periodically, such as for tetanus or hepatitis, and then pay you extra for participating in that program. There is at least one near us that pays the donor by volume and the way to give more volume is to weigh more. Really. There are age limits and health limits. For example, most will not take anyone who is an insulin diabetic. I have no idea why. I started donating blood to get over a fear of needles caused by the power of suggestion over a chance comment by a nurse. The first time I showed up, I read about the side effects and went blind in the waiting room. I didn't feel the fear emotionally but my body did physically. They had to take me to a couch to lie down until I could see and go home. I went back the next time and donated probably about 60 times after that. After every 20th donation, they paid an extra $20. I didn't get in on the special population program because I didn't know about it fast enough. I quit because my husband thought I was donating too much and might hurt my health.
If you live in a large city, you may qualify for Legal Aid. A lawyer might help you maneuver through the child care situation by eliminating any problems ahead of time. The rumor around here is don't contact any government agency without having a lawyer or you'll probably get nowhere.
My printer runs out of toner at about four reams of paper.
Flash, thanks for the financial information. I had a question but when I went back over your comment, I couldn't find the part I didn't understand.