I went to IFA this weekend to price out chicken supplies (Utah, fall of 2013). Here's what I found:
Chicks ($4 from mypetchicken.com plus shipping $36)
chick feeder $2.49
chick waterer $1.75
chick food 5 lbs for $6 or 50 lbs for around $20
Chicks eat about 10 lbs of food per chick for the first 10 weeks. For my 3 birds, I'd need about 30 lbs of starter feed. So costs for the chicks is $43 not counting the chicks themselves plus the bedding plus the electricity to run the bulb (I might use news paper and boxes which would be free to me).
oyster shells 3.09
chicken food $19.49 for 40 lbs
pine shavings $11 for 12.5 cu. ft.
metal trash can (to store food and bedding)
Coop $250 ?
So initial costs of chickens is $44. Chickens eat about 1.5 lbs of feed per bird per week, so I would need 4.5 lbs of feed a week. So food would run about $9 a month. Shavings would be about $3 (assuming 16 sq ft coop, and having to add 4" a month).