Please don't think I am being mean, But that really is to long to leave ANY dog on a regular basis. Think what kind of life they would have alone,bored, have to go the bathroom for hours on end. That is no life for them. Honestly you don't have time for one at this point in your life. I totaly understand you wanting to get one. I did to. But I had to think of the yorkie and not myself. I waited until I was retired, kids grown, I devote all my time to Andy except for the odd time I have to do something without him (groceries).
They need fresh air and excercise, walks activities you can't possibly do that from work. So please think about the puppy first.