Here is a good thread to read through.
http://www.cornsnakes.com/forums/sho...d.php?t=126082
There is a lot to consider like feeding and housing the babies. What to do with deformed or non feeder babies? Do you have a source for selling babies? You've already mentioned you would only be producing normal with hets. In most markets they don't sell very well.
A lot of breeders are happy to break even.
I've only breed for one season. So far I'm only doing it for fun and because I enjoy working with the animals and being friendly to customers at local shows. My biggest cost savings was breeding my own rodents. That also has upfront costs that you need to take into account.