
I always give puppy owners a page on vaccinations, and why I won't do them before a pup leaves home. It's part of the information pack that I give when pup is chosen, so they have the opportunity to get a pup elsewhere if they so choose.
I did have a couple that had a pup reserved from well before it was born, but when she found out that I wouldn't vaccinate at 6 weeks, she cancelled. Not a problem.