Definately size..when I first saw an ad for a yorkie it was way over a decade ago. It said they would be 4 lbs and $900. Back then, $900 for me was an unattainable amount, heck it was a car! I couldn't even imagine a 4 pound dog. I always said that someday I would have my dream dog of a yorkshire terrier. I even bought a book on them. Now I have her, she cost more than $900 but weighs less than the 4 pounds I couldn't fathom. She's so full of personality that even under 3 pounds I don't think of her as that small
