I have no help for you in this department, I don't keep track of how much I've invested compared to what I get back. However, I sell my eggs for $3/dozen here, which is on the lower end of what they go for. In fact, if someone gets two dozen at a time, I sell both for $5. That being said, there are others around here that sell theirs for $5 or more per dozen. I'm just venturing into the meat chickens now, will be doing the first big butcher in about six weeks. The CornishX meat sells for $3-$5/pound, according to local sellers. I think I will be starting this years off at $3/pound, see how it goes. HOWEVER, I invested ALOT more money into my coop, run, supplies, and food than I will likely ever get back out of it. For the meat birds, I just bought an electric plucker, and am feeding them much more food than my standards eat. I do not sell my eggs for hatching as I have a backyard mix. Money wise - I will definitely not be retiring on chickening income. But they sure are fun!!!
A person who does track their expenses and sets their prices to make a profit can't compete with this. It isn't a criticism at all, just an illustration of what I see in my neighborhood as well and why it's hard to make money with backyard poultry. I do have a neighbor who has an egg contract with a commercial supplier. This is a better deal in a way because he has a guaranteed market at a set price and doesn't have to compete with his neighbors. However, the expectation is that he delivers the agreed amount on time consistently. This becomes a problem during molting and bad weather and he has to increase protein and light, adding to his expense. He doesn't make a profit either but he said it "helps" pay for feed for the rest of his flock.