The location is ideal, right in the heart of the old centre. You can reach everything with a few minutes walk and the view on the duomo is breath taking. Even the entrance looks like a museum !
Gianmarco is very reactive and welcomed me very kindly. I would go back to his place without any doubt.
The room per se has minimal comfort but you won't lack anything (although you can hear the other guests quite clearly but it didn't cause any trouble during the night !). Anyway, with all the wonders the area has to offer, you probably won't spend much in your room !