Hi There!!
I think it depends on the dog, some may say all of them are yappy or bark alot but from my own experience my Stormy is not yappy at ALL. She hardly ever barks unless there is a knock at the door or if we are at my moms house and ALL the dogs get rallied up from seeing something outside, then she will join in. Besides that the lady underneath me in my Apartment building didn't even know I had a dog til the other day when she saw us outside and I've had Stormy for about 7 months now!
My moms yorkie on the other hand, barks pretty often at anything lol