There are so many thing to consider when thinking about getting a puppy. One thing that I think should be at the top of that list of things to consider is do you have the time. You need to make sure that you have the time and can be there to provide proper training during those very critical early puppy and adolescent times in a young pups life. Because without that you will end up with a resistance on your hands with a stubborn and ill mannered/untrained pup. You will want to consider the amount of time that you will be away from home and have to leave the pup alone and unsupervised. Someone needs to be there to take care of the pup, to make sure he is safe, fed and trained properly.
Plus I think my biggest think with apartment dogs/pups would be the yappy thing. I think that it is important for you to consider your neighbors. Especially if you will be gone for more than 4-5 hrs a day. Puppies do not like to be left along. Being alone during a critical time in a pups life can cause anxiety issues among other behavior problems. A young pup needs time to get use to their new surrounding after leaving their mamma and litter mates. It can be and usually is a very stressful time for a new pup. Not to mention your neighbors who are home to hear it.
You have to consider the time and energy it takes to train a new pup. Training doesn't happen over night and each pup progresses at different levels. Some, do very well and than there are those pups who just can not handle to transition from being with mom & siblings to being alone and confused.
So, weigh your option and if you have the time, effort and ability that it will take to care for and train a new pup than go for it.
Here are some site that may be helpful:
How to Care for a Yorkshire Terrier | eHow.com Dog Breed Selector and Puppy Finder | Eukanuba BreedMatch