For the last couple of years we've hatched eggs bought off ebay in an unsophisticated incubator. In 2012 we left it until June and hatched in July, which did not produce a spectacular bird, albeit female. In 2013 we had a male and a female hatch in April. The male reached 20lbs (dressed weight) easily with no special attention by early December. The female was roughly 12lbs once dressed. They ran with our chickens and were lovely company over the summer.
We paid roughly £1 per egg and maybe £10 each in feed (usual stock of chick crumbs, layers pellets and turkey finishing pellets), and dispatched and dressed them ourselves. Very easy to do on a small scale basis.