A lot of it depends on the individual dogs temperament. My 6 year old Yorkie is a rescue and she never barks. She only barks at the door bell on the tv! She is very mellow. My other Yorkie who is 5 months hasn't been too bad but she is still young. She barks at stuff that makes sense, like loud noises, thunder, playing...and even the ironing board
. But I consider my 5 month Yorkie to be pretty mellow and a great lapdog.
Now my sister has 2 havanese dogs. They are very yappy! The girl has a lot of anxiety and is constantly on the run barking at anything and everything. She also pees everywhere even though she's 2 years. She is good with kids though and a good lapdog. The boy...is huge! He is almost 20 pounds and is not good with strangers. He bit my dads leg :-( but he was easy to potty train. I also like the Yorkie coat better. My sisters girl havanese has very stringy hair which isn't the most appealing. But the boy has very curly hair!
Yorkies are very very smart and they know it and will test you! I seriously feel like I'm talking to a kid most of the time because they understand what I'm saying. Both breeds make great small dogs but their personality will be determined with how they were bred, their temperament, and the environment in which they are raised. I live with my boyfriend in a small apartment with little noise and definitely a much calmer environment. My sister has 2 very loud kids which causes the animals to act out. Good luck!