I would guess price would be determined by current market value, supply/demand and reputation.
Take a look at piedbalds for example (well, I did, hehe). Generally, the price for hom. pieds ranges from $4000-7500. The most expensive I've seen are from Pete Kahl - but that makes sense (to me anyway) since he is the one who proved out the morph. If I wanted to breed pieds and bought a pied from the Pete Kahl line, I would think that would say something. Dunno, just my hunch. Lesser known breeders then don't charge as much.
From reading what Adam posts, there is still a bigger demand than supply for most morphs and breedable and/or proven breeder adult normal females.
When a new morph comes out or is still super new, the prices are set really high...because the market will support those prices. Why wouldn't you sell your product for the highest amount you can get for it? =)