I do not understand the mathematics behind the dilemma. I'm assuming only the firts chicks cost money, because down the line they will breed.
But feeding them, housing them - vitamins and doctoring costs a lot of money.
So anyone with couple or more chickens - how much does it cost to have them on the table? And realistically how many eggs do you get?
The old breeds you just release around your home, that's it. A coop helps if you want eggs, but the goal here is to eat chickens not eggs. And it costs zero upkeep. The chickens are too stupid to realize you're a predator, but capable enough to avoid natural predators. They'll just hang around your property, because you keep normal predators away most of the time.
That's how the arrangement with chickens is supposed to work.
If you're in a city or even a town and can't let them loose and just want eggs, then you still don't need vitamins, just raise mealworms and feed them that with chicken feed.
But you're going to need to make sure you buy the right kinds of chickens for what you want them to do.