I just want to know how much training in nutrition did you receive? Everyone here says that vets know nothing about canine nutrition. Maybe you could join a few online food forums and learn something!
(Sorry, I couldn't resist.)
Seriously, I think if someone is going to be gone most of the day, a Yorkie isn't the best choice. If you decide that that is the only breed for you, then I would look at an older dog, one that was a bit more independent, or you could do like some have done and get a couple of them so that they could keep each other company. I would think that your job title would be a plus.