I think both the breeders' enviroment and yours will play a part. Tia was quiet as a mouse when we brought her home. Recently, she's started the "Yorkie squeek" and this low gutteral growl that Sandy has taught her (I'm not kidding, she sits there trying to mimic Sandy - it's so funny - her's is just more high pitched...) She's started barking now when I leave the room or when I come home from the grocery store. She'll give me one bark if she wants me to throw a toy!
I think it's cute, not excessive.
Anyway, good luck! My mom was able to "train" her lhaso not to bark using the "no bark" method mentioned above.