I haven't sold any of our eggs, but I can tell you how they were sold when I purchased them from a local breeder here. The woman posted them on Craigslist at a price of $15/dozen for button quail. Since I was just starting out, and didn't want to go for the whole dozen, I was able to get three eggs for $5. She had small plastic cartons used for quail eggs that she got from our local natural foods co-op. If you ask, maybe you can get these from your local store as well, or let them know that you will take the cartons before they toss them out with eggs that break in the store.
If I ever get that close, and the Mrs allows it, here is my plan: I will be getting a business license so I can conduct business within the city limits. Then I plan to reserve a table at the local farmers market. I feel kind of lucky because where I live there is a farmers market 5 minutes from my house, and another one within a "frisbee throw" of the University of Alabama campus, which is a 15 minute drive. I've been to both, and none of the farmers knows of anyone who raises quail. Each of the farmers markets are open from 5 am till noon on Saturdays, and if I'm lucky, I'll only have 3 or 4 cartons for sale. I'm not going to price them so I can make a killing; I will sell them for a reasonable price to help pay for feed. By then, I'll have some egg cartons for quail eggs.
That is, of course, if the "Mrs allows it". When I first mentioned the idea of raising quail, she was "more impressed" by the benefits of the eggs than anything else. She even devised a plan where she would find out the quail egg equivalent of a chicken egg so she can freeze the eggs in containers for future use.