A breeder that would release pups at 6 weeks is not concerned about the cost of the shots or wormings. Those are minimal expenses that could easily be added to the price of the pup. He simply can not be bothered caring for them after they are weaned and therefore wants 'em out The momma's do all the hard work up to that point and then the breeder has to deal with feedng and poop. Huge red flag! Pups should stay with the litter until 12 weeks/10 minimum to learn socialization skills from each other. This is a crucial imprint stage of development and you should steer clear of breeders who release earlier. The site
www.buyingapuppy.com has a good list of questions to ask a breeder when choosing a pup. Nobella already clued you in to ytca. You can also check with local kennel clubs and rescue sites, there are many listed on here if you use the search...and the prices are much easier to take.
oh and Welcome to YT!