1. From somebody at a flea market, or selling them out of the back of a truck in a parking lot. Chances are these pups are from a puppy mill (see below). The pups may even be stolen. Once you and the seller have parted you have no way of contacting them again if there is a problem, and there very likely will be one if this is how they have chosen to market their pups. You should always be able to see, and meet, the parent dogs, and inspect the facilities. With this circumstance you can do neither. This is a “fly-by-night” rather anonymous, shady, deal. Avoid it.  Report anyone selling puppies in a parking lot to authorities, very likely it is illegal in your area.  Do not let them know you are reporting them, pretend you are calling another family member down to have a look.

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   From the Internet. You can easily find litters of pups over the Internet, the seller will even offer to arrange shipping to you. However if you cannot go to the home of the pup, meet the parents, and the seller, this arrangement should be avoided. You just can never be sure, and might end up losing your money on a pup that requires additional health care expense, or might not even get a pup in the end.  No reputable breeder sells pups in this way.  They usually have waiting lists for pups for sale, and never have to advertise a litter. 

3. From a Puppy Mill. If you go to a persons home or property and it is filthy, overrun with dogs, or where the dogs are kept in tiny cages, this place is a “puppy mill” it is easy to think you are saving, or rescuing a pup when they take it from such conditions. But, if money was exchanged, then you have just rewarded the person for breeding and keeping dogs is such fashion. In many places puppy mills are illegal. Even if you took the pup for free, not only might you end up with a sick puppy, but you have ignored the plight of the other dogs. The best thing to do is leave and call the local animal control authorities.
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4. From a Pet Store. Make no mistake, pet stores do not get pups from reputable breeders. Why would a reputable breeder ever sell their pups to a pet store? Who would need to hide behind a store front to sell puppies? Pet stores will not admit it, but they do buy pups cheap from people who breed purely for profit. The puppies are marked up by the store and resold. They might be registered, but registration is not proof of quality. Pet stores often fudge, or omit, some important details of a breed just to get a sale. Because the pups were produced cheaply they are prone to genetic problems which may show up later in life.

5. From a Back Yard Breeder. A back yard breeder is anyone who puts an advertisement in the local newspaper about a litter of pups for sale. This is somebody who produces litters intentionally to make some cash. If they only have one, or two, breeding dogs they are a back yard breeder, if they have more, they are a puppy mill. Back yard breeders who sell pups that have not been checked by a vet, dewormed, and vaccinated, should always be avoided, you might pay for a pup that has a heart (or other) defect. Back yard breeders do not breed for quality (see Reputable breeder below), they usually do not offer any kind of health guarantee.

6. “Free to Good Home Pups”. These are typically the result of an accidental breeding, and the owners are simply trying to get rid of the pups quickly. These are somewhat on par with back yard breeding situations, except you are not paying for a pup that might have problems. It is a “take-at-your-own-risk” situation here. I never support or encourage taking of free animals, because when compared with adoption (see below) they cost more in the long run for you to have the medical requirements done. Additionally I feel it makes it too easy for people to ignore getting their dog fixed if they have an easy time getting rid of the pups.

7. Adoption from a Shelter. I am certain that many people feel this is “the best” way of getting a pup, and I certainly support it whole-heartedly. I have put it as second best solely because so many adoption pups are mixed breeds, and the only concern with a mixed breed is you don’t fully know what to expect as far as size, temperament, and genetic problems, go. Shelters and proper Animal Rescue groups often adopt out litters of pups. They vaccinate, deworm, and have the pups checked by a veterinarian. While they cannot offer the same kind of genetic guarantees as reputable breeders (see below), they usually offer a ten day, to two week health guarantee. Shelters are honest, they care about getting a good home for the puppy as much as they care about you getting the right puppy. As non-profit societies, their prices are usually very reasonable considering all that has gone into the puppy.

   

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8. Reputable Breeder. A reputable breeder is one that has taken the parent dogs to shows to prove their worth as breeding animals. They have had them checked by veterinarians for possible genetic problems, often eyes, ears, and hips. They do not breed unless they have a waiting list for pups, and always stand behind their dogs for a lifetime against genetic problems. A reputable breeder will make sure the puppy is the right one for you, they will take it back if at anytime you cannot continue to provide care for it. Reputable breeders care about improving the breed, so while their costs may be high, it is not because they are making profit, it is because they have invested a lot in proving that their dog was worthy of breeding. Reputable breeders breed only purebred registered dogs.

More on Dogs:

What Happens to Pups that Pet Stores Cannot Sell?
More information on Puppy Mills