I dunno about the cost. I'm thinking that the breeders probably have "mates rates" for people they like. Hence I'm really hoping you give them a chance before rushing off to gumtree.
Someone toted up the DNA tests, the vet costs, the puppy raising costs, the show costs, the ANKC registration costs and etc - and it did come to over $1000 a puppy... So anyone selling their puppies for less is skipping - probably on vet and show/ankc costs, mostly vet costs. So you might get a puppy that is not vaccinated or microchipped or wormed from parent dogs that are not microchipped or vaccinated... parvo risk is high... worm risk is high etc.
Rescue is a bit different because they get donations towards vet bills or vets give them discounts on desexing and they don't often pay much for the dogs that are already of no value to their previous owners for various reasons. So they can afford to sell just to recover their costs and they don't have the same costs as the ANKC pedigree breeders.