[Lorraine]

Find someone local don't buy from the Internet having whatever someone tells you they are selling shipped to you. Visit the breeder, see the dogs and puppies, you should be able to see at minimum the Mother to the pups. Don't buy from someone with several breeds
The seller should be asking you many questions about the kind of home you can offer a pup and you should be asking the seller many questions regarding the care of the puppy, background on the dogs.
Don't buy from a broker. A broker is someone who sells puppies for people who breed and have often never seen the puppies until they are sold and certainly never seen the parents.
You want to buy directly from a breeder. Ask about guarantees, you can ask for references. There should be vaccination, worming, health records on the pup.
You should be able to take the pup to a Vet within a few days afer purchase and be able to return it if the Vet has found a health problem. It must be in the contract, verbal isn't good enough.
Good luck
Lorraine
Loriben Yorkies