The apartment is located in a great neighbourhood with a street that has little to no cars going through so the area outside the apartment is very quiet.
The apartment itself is a typical Airbnb... almost everything is from Ikea and the beds are pretty hard and cheap feeling. A top layer on the mattrass would easily fix that.
Also you can hear a lot of noise coming from the communal staircase of guests leaving their apartments/talking, and the elevator... which is annoying if you are a light sleeper. Inside the apartment is a long hallway, an easy fix for this noise would be a double door (like they have in most hotel rooms).
The communication with Jacopo was great! He was very attentive and responsive during my stay.
All in all it's a decent Airbnb to stay for a few days, but they can invest in a little more quality... especially for the price you pay per day during the summer season! I definitely stayed in more quiet and comfortable apartments in Barcelona. I give it a 7.