Don't Buy Until You Think About...
Before you buy a puppy, there are a number of considerations before you commit to buy that can affect just how successful your relationship with the dog will be.
The Pedigree
How important is the pedigree to a dogs potential? You need to consider the pedigree very carefully. A lot of show champions without field trials showing in the immediate couple of generations may indicate that the dogs are not worked, but there is no guarantee - a lot of working dogs do not enter trials. On the other hand, a lot of field trial champions in the pedigree may mean that the strain is 'hot' - fast and intelligent, and maybe difficult for the beginner to train.
The Environment
Is the kennel clean? Is there a lot of mess around? Are the dishes clean, with no drying food around? The odd piece of mess is fine, but go by your gut feeling.
Other pups in the litter
The ideal situation when choosing a pup is to have the choice of the litter. Check out not just the better pups, but the state of the entire litter. If there is the odd small one, okay, but if the entire litter is variable it would be unusual.
How to pay
Before you go to see a litter with pups that are ready, speak to the owner about payment - some like cash!
Puppy Farms
There has been a lot of bad press about 'puppy farms'. The main disadvantage of large scale breeding is the lack of socialisation of puppies. However, in principle as long as puppies are properly socialised during their early days, breeders with two or three litters should not be a cause for concern.
Where to meet
Always be careful if the breeder tries to arrange a drop off at a train station or motorway services. There will be no opportunity to see the parents, and there can be emotional pressure to take the dog regardless, since the breeder can argue that they have spent time and money coming to meet you. Along the line of 'no time-wasters' this is not a sign of a low pressure viewing, more of the hard sell.
Breeding constraints
Breeders used to (and may still be able) to prevent certain actions on the owner of the puppies - these used to include being able to prevent a puppy from being shown or bred from.
If this is mentioned by the breeder, it is important to find out why. Personally I would not be prepared to buy a puppy unless at a huge discount with constraints like this.