Yes a good market can bring in some cash, The first year I did the market here, I did not have salsa in the stores and I would routinely sell 80-100 pints of salsa on a Saturday. But $37 for 12 eggs?!? Sheesh! Unfortunateley there's only 1 market in our area, so the multi-market option isn't available.
Also, here's something interesting........the first year I sold salsa at the market, sales were GREAT. So in the fall, I got the salsa into the 2 local grocery stores and maintained good sales through the winter. Next spring...I'm back at the market and sales STUNK! People would come up and eat samples like crazy, and then say, "this is the BEST Salsa! I just bought some at the store!" So after 3 summers, I quit selling the salsa at the market. I miss that nice chunk of cash every week. It definitely helped with the groceries while the other business was getting going.
NJA, what you say confirms what I was saying also. The people are inspected and instructed on safe food preparation. Education is key. A person may have the best family secret recipe in the world, but if they don't do it safe, it's all for naught.
I consider my enterprise a cottage industry. For the first 10 years or so, I used other kitchens and just did the markets and a few stores. 4 years ago we were faced with the decision to either build our own kitchen or quit making salsa as the other kitchen was no longer available. And our other business was to the point where I really didn't have the time to deal with working out of someone else's kitchen. Fortunately, we had enough cash and I also had the opportunity to cater picnic lunches for a river rafting company for two summers. That chunk of change paid for the kitchen in 2 summers.
The point is, I worked out of other facilities for 10 years. Minimal cash outlay. The most expensive thing I paid for in the first 10 years was a used DittoDean continuous-feed food chopper. ($750 for a 20-year old used chopper...YIKES!) and I didn't need that for the first 5 years. The first kitchen I used had a chopper available, but after we moved to eastern Washington, the next kitchen did not have a chopper. My business is still a cottage industry. It's a part time interest and the refrigerated products are only in 2 local stores.