The dogs do not receive health examinations and are not vaccinated or dewormed. A dog is often sold to a notably cheap price. Most often, a puppy mill customer will end up paying a veterinarian many times more than he or she “saved” in the purchase price.

The pups that puppy mills produce are in weak condition because of bad treatment, poor-quality nutrition and lack of vaccinations and deworming. The breeder suggesting the buyer to take the puppy home right away is a definite red flag. Unlike a responsible breeder, a puppy mill breeder is selling the puppies in a hurry to hide the puppy's health issues before it arrives to its new home. The puppies can already have suffered permanent damage and may not develop into normal adults or, in the worst-case scenario, they'll contract a contagious disease, which the vet cannot cure.

A puppy mill will often house its bitches in cages and make them function as pup-making machines, possibly breeding them each time they are in heat. This is a great strain on the bitch. Some puppy mills will register part of their litters with the Finnish Kennel Club but will produce an unregistered litter the next time the bitch is in heat. In order to have a litter registered with the Finnish Kennel Club, more than 10 months must pass between the litters of a bitch and the bitch is not permitted to have any more than five litters over its lifetime.

Even if you feel sorry for a pup being brought up in poor conditions, you should never buy one out of pity! You may save one pup, but you are also supporting the activities of a puppy mill at the same time and the dogs will keep suffering. If there are no buyers, these unscrupulous sellers will soon disappear as well.

Many puppy mills advertise their pups in the same places as responsible breeders. The shadiest breeders are usually absent from the breeder listings of the breed clubs, however. It is best to be sceptical of any vague claims about unregistered and unplanned pups, as breeders are allowed to register only one accidental litter with the Finnish Kennel Club.

Puppy mills will often try to use accidental mating as an explanation to why they don't have, among other things, health examination results, even though their actions are planned and they exploit dogs, which are too young or too old, just to make money.