If you're just talking about price, I don't think you can beat the price of factory farmed meat, eggs, and milk at the grocery. Now if your animals produce enough extra that you can feed yourself and sell the excess, you might be able to break even. But with regulations on dairy, meat sales, and even egg sales, they make it very difficult. I mean, if there were no laws and you were living in the back of your van in a anarchic zombie wasteland, then you wouldn't have to worry about breaking any laws - but then there wouldn't be any factory farms or grocery stores either - so you would just do the best you could.
It's actually quite interesting to study other countries and see how people who are still living closer to the land handle their farms, producing their food, and preserving their bounty so they'll still have some in the lean times. Read up on Mongolians sometime - many still live nomadic lives in tents with no electricity. Now that's living off the land!
