Good breeders think ahead and make reservations in advance for the puppies they will produce. You may have to wait for a puppy, but that's not a bad thing. Beware of someone who first creates puppies and then worries about how to disperse them.
What does the breeder do for a living? Dog breeding should be an avocation. Avoid anyone who makes their living through breeding dogs! The corners they cut financially may be at your expense.
Are the premises clean and orderly? Are the breeder�s dogs healthy in appearance? It can be a messy proposition to raise a litter of puppies, but puppies should not be wallowing in waste, covered with fleas, or otherwise appear neglected. Keep in mind that many longhaired bitches will shed their coats heavily during this time, so if the puppies� mother appears a little ratty it is not necessarily inappropriate or unusual.
Do you like the temperaments of the puppies' parents? Remember, temperament is genetic! Avoid puppies from bitches that demonstrate any aggression or shyness. Specifically inquire about possessiveness (food and object guarding), inter-dog aggression, defensiveness about being handled, etc. Accept no excuses for undesirable behavior. Don't be afraid to ask the breeder to demonstrate the bitch's good temperament to you.
Has the breeder or will the breeder allow you to temperament test the litter? While puppy-testing is not especially predictive of adult temperament, it�s an attempt to gauge a puppy�s personality so that it can be best matched with a new owner. Ask the breeder's permission before doing anything to a puppy. No potential buyer has the right to do anything to a puppy which a breeder perceives as potentially harmful.
Does your breeder respect veterinarians, trainers, groomers, breeders, and other peer professionals in the dog world? Beware of breeders who are paranoid or hostile towards other professionals. One cannot operate competently in a vacuum, and in general, good breeders are socially well-networked. They are liked, like others, and respect competent professionals in their field. A good breeder should make the effort the know other good breeders (especially of their own breed). It is important for a breeder to strive to improve their knowledge and understanding of their breed and submit to peer critique, even if it is not necessarily formalized (as in the show ring).
Beware of fads and people who ascribe to them. Some people feed their dogs a diet of raw meat and bones and avoid vaccinating their animals, for example. These people strongly believe that commercial kibble and routine vaccinations create immune system defects and compromised health in pet dogs. Perhaps that�s true for their dogs, in which case they should not be breeding those animals. Find a breeder who feeds a good quality commercial kibble and provides standard veterinary care, including appropriate vaccinations, heartworm preventatives, etc.
Often overlooked, but important - do you like the breeder? Will you feel comfortable relying on this person as a resource to help you if you ever run into problems with your pup? If you feel that the breeder is abrasive, rude, ignorant, or otherwise disagreeable, look elsewhere to buy your puppy. One of the greatest advantages of buying from a breeder is the support and assistance they can offer you throughout your dog's life.
Good luck in your search for a breeder. And if this all seems too complicated, swing by the local pound and pick up a good, old-fashioned, all-American mutt puppy!
Source:
Evaluating a Pet Dog Breeder