Pietro apartment is very good place to stay when visiting Trento. My wife and I stayed there for a full week and we don't regret a moment having chosen this place.
Before arriving, we received detailed instructions on how to get to the apartment, their rules, etc. Pietro waited for us and explained personally how things worked, etc. So check in was smooth and easy.
The apartment is in a nice area, very secure, quiet and only 10 mins walk to the city center and 15 mins to the train station. The views from the balcony were fantastic but we couldn't enjoy the balcony because there are currently working on the exterior of the building. I suspect the works will end sometime soon.
The apartment was spacious for two people, with a small kitchen with all you need to cook your meals. The bedroom and the bathroom were also spacious.
Everything worked fine during our stay, so we did not have to communicate frequently with the hosts but Giuseppina, Pietro's sister, was always prompt in responding.
Without any doubts, I would stay again in this place.