We live in a condo building in NYC and we just adopted our yorkie pup a couple of weeks ago. He is 4 months old. Thus far, we have not had a problem with him barking at all while we are home. When we leave the apartment, we put him in his playpen. In his playpen, he has everything he needs...pee pad, water, a little food, his crate, a toy. When we come home, we can hear him barking from the elevator, and we have no idea how long he has been barking! Has anyone experienced this and have any insight on how to prevent this so our neighbors won't hate us?