The barking was a real challenge
My Pomeranian barked at everything for the first two years. The postman, the wind, birds outside, the television. My neighbours in my building were patient but it was a genuine problem. We have worked extensively with a trainer and he is now manageable but without that investment the barking would have been insurmountable in our living situation. Anyone in a flat with close neighbours should plan for bark training from day one.
Pomeranian