I congratulate you on your informed decision. I know you have made the right one for you.
I'll have to say though, that even though the Yorkie breed is a lot of work, I have never ever been so "taken" by any pet, ever. I am NOT a dog person, we have had various dogs as I was growing up and even after I married. They were always my hubby's dogs, I didn't pay much attention to them at all.
All that changed when we got our first Yorkie. OMG!
I am completely in love with these guys (we had to get another one!). So, while I agree, they are lots of trouble and worry, they are expensive (but I didn't pay nearly as much as you were quoted), my guys have been healthy (knock on wood) and I can't see myself ever having any other breed of dog.
Good luck with your new puppy! I know you will have lots of fun!!!