from what I've read on this forum, it depends on how much goats are selling in your area, and whether they're registered or not. check craigslist and other places where livestock is sold to see how much you can ask for your goats.
I agree, check Craigslist to see what others are asking. Here in NC a mixed breed doe can go for up to $175. But of course, price should depend on quality. If the parents aren't that great on the genetics scale I wouldn't bother selling for more than $75 and for pet purposes only.