I just did Cornish Cross, started with 75, ended with 58.... they have about a 30 % mortality rate...  I spent $495.20 total, not counting the packaging to freeze them all..... it was about 1.71 a pound which is expensive when I can get roasters for .99 a pound in the store, probably will not do again as they are dirty, don't care to forage, die easily etc.  I don't get a lot of satisfaction out of going out in the morning to find a dead one, it's like throwing money away.  Grain here is $14.50 a bag and that is the cheapest (game bird feed).  I am assuming that commercial chicken farms get a lower cost on grain as they probably own the grain companies as well, this is how they can sell at the price they do, there is no way to raise them cheaper then in the store, someone above said .75 a pound, they either get cheap grain I can't get here or they produced extremely large birds.  Either way, my experience wasn't beneficial enough for me to do it again.... seems the commercial producers have us over a barrel, it is not cheaper to produce your own meat these days and even so, you are not producing the grain, therefore you really can not have peace of mind.