I know how exciting it is to be bringing home a new puppy soon, however, waiting 12 weeks is reccomened for the yorkie breed. Mainly, because these puppies are so tiny that there is a chance of them developing Hypoglcemia. When they are stressed out , such as going to a new home, they often will not eat for too long of a time, which is dangerous.
Also the socialization takes place with their litter mates and mother. If this time is missed then the puppy may have problems with biting, and trust .
I got my Suzi at 9 weeks. I did not know that I should have waited. Also, your baby might even be a little younger then expected.