raising eggs as a sole business venture is tough going. It really depends on how much you want to earn. The profit margins are thin on eggs.
Do you have capital to invest in this project? In my experience, you'll want to raise a few hundred dozen a week to really make any money. You're talking 1200 eggs a week minimum... That's a lot of birds. Free ranging a lot of birds requires good fencing, water access, coops/chicken tractors, feed etc etc.
Before all that you need to consider your market. Are you selling out of your home, wholesaling to restaurants/university etc? Farmer's market?
what about insurance? egg inspection? There's a lot to it.