Prices change each year so by the time you actually produce a BEE they could very well be $100 each.
Price are based on sex size but also quality.
Finally remember that no matter what the price if you do not have a solid reputation your snake might not sale for the asking price or it might take you much longer to do so.
At this point do not worry about pricing enjoy raising your animal and breeding them, establish a reputation and worry about the price when you actually have animals to sell.
Remember do not count the hatchlings before the hatch
As for idea in prices browsing through classified as well as breeder's website will give you an idea on how to price your own animals when the time come.