The apartment is even better than in pictures and the owners are very kind and helpful. We arrived on Sunday and they had bought for us a bottle of wine and something to eat and cook because supermarkets were closed. However, pay attention to some tricky things of the advert:
For example you have to pay 50€ cleaning fee in cash at your arrival together with 150€ deposit.
The apartment is not at 10 minutes from the Duomo unless you take a bus. The bus ride is 10 minutes more or less once you catch the bus.
The check out was at 10:00 in the morning because someone else was coming to the flat.
In general the experience was good however, if I had known the cleaning fee and the very soon check out I would have rather paid the difference of staying in a more central hotel.