My wifes uncle is backgrounding about 750 hd right now. He contracted around 530 from a feedlot for a price per head per day or pds per day whatever is greater, bought 180 of his own and about 30 second trimester cows that he will calve out and sell as pairs in late spring. The feed lot trucked in the thier cattle and paid for shots for the whole herd when they started to lose some calves. All the calves from the feed lot were heifers except 1 pot load of steers. Hes running the calves for 100 days or so before the wheat really starts growing again. He bought futures on his calves as well. He has all the equipment and a ton of winter wheat and some corn stubble. Biggest input would be hauling water. Not any different from the rest of the cattle industry, try to buy at the right time, put weight on them and hope the market comes up when your ready to sell. Be flexible and dont have all your eggs in one basket. Its a lot of work building fence taking fence down and hauling water. You could see a higher rate of loss depending where or how far they come from as well. Buying quality and uniform calves make a bigger difference when you go to sell them and they usually grow better. There are a lot of variables as you stated and I listed what I thought might help. Scott