Person cannot or will not show you the mother of the puppies. You may be told the mother 'doesn't like people', 'is at the vet', or given some other excuse as to why you can't see her. Person denies breed-specific hereditary health problems exist, claims not to be aware of hereditary health problems, or claims their dogs are immune to hereditary health problems. Person can 'get you any breed you want'. Person does not want you to see where the puppies are currently living.
Puppies are dirty, lethargic, appear sickly, or have discharge from the nose and eyes.
Person encourages you to take home a puppy younger than 7 weeks old. Person tries to tell you that AKC papers mean that the dog is of exceptional quality or exceptionally healthy. AKC papers simply mean that the puppy is registered as a specific breed because both of its parents were registered as that breed. Papers are no indication of health , temperament or quality of a dog. Person selling the puppy takes charge cards, is having a 'sale', or uses high pressure sales tactics to make a sale.