One of the most important decisions is picking a reputable breeder. It dramatically improves the odds of a healthier dog. But how do you know?
Pick a breeder that is actively trying to improve the breed-versus just selling puppies*. Interestingly, you often do not pay any more for a pet quality dog from a "Quality" breeder.
* backyard breeders (often nice people) breed from poor stock as can not breed to top dogs and do limited or no health checks.