Small dogs tend to have barking complexes. It's the only super power they have. I agree that owning a dog in an apartment is going to be tough, but if you plan to spend a lot of time with your friend you can definately make it work. I lived downtown Portland, OR for a couple of years and my neighbor across the hall had a little dog. Barked like crazy... so she was lucky it didn't bother us. It also ate her kitchen floor one day because it was bored and she left it home alone too long. I had a dog that ate a hole in my wall as well... so puppy proofing is not always possible

Just a warning.
Since I always recommend adopting, I would call your local shelter. Tell them what you want the dog for and they can tell you if they have a dog with that personality. Since they examine the dogs and do behaviour training, they will know the dogs personality in advance.