Hi and Welcome to YorkieTalk!
I agree with all the ladies who suggested that you wait until a puppy is 12 wks old. I have 2 Yorkies and got them both at different ages. I can't begin to tell you the difference in the two. Every pup has it's own personality but that's exactly why the puppies should be with their Mom and littermates. They learn and develope so much during that period. Sure, some may be just fine leaving early but they could have been "better" with that extra time in the litter. To me it's kind of like when you have a child that "could" go to school the next year but really isn't ready and "should" wait until the following year but the parents decide it's cheaper so send them to school now instead of paying for daycare one more year.