I'm not sure if I want to do the math out like this and know, but let's see...
Est. Cost of building supplies to partition part of the shed and construct exterior enclosed run: $350
5lb. Bag of chick starter: $5 (i think? Yes, I know i got ripped off, because you'll see below

20 Lb. Bag of chick starter: $8
Aluminum Waterer, 2 gal: $20
7lb Feeder: $11
Chick feeder and waterer with mason jar: ~$8
Extra plastic waterer for outside in run: $4
50 Lb. Bag Chick Grower: $12
50 Lb. Bag Layer Crumbles: $12
50 Lb. Bag Layer Pellets: $12
2 Bags Pine Shavings: $15
2 Bags of grit (chick and adult) $15
50 lb. Bag of Scratch Grains $10
Red Light Bulb: $10
I'm going to throw in an extra $25, for all the whats-its and whos-its that have been picked up along the way, like the hardware for the lightbulb-water-heater, etc.
Total: $517. My four Buff Orp chicks were a birthday present, so I wont count the cost of them, although its negligable. I also wont add in the cost of added electricity that goes into the coop.
I've been getting about 2 dozen eggs/week for 5 weeks, that's 120 eggs.... I'll call it about 135 eggs, because there was a sizable gap between the first layer and the last one.
$3.83/
egg! or about $46/dozen. Crap, wish I hadn't done this out! Haha. Good thing I'm dooing this for fun and not for profit. I don't sell the eggs.