NO AC in the bedroom! There is an AC machine on lower level, but it does not reach upstairs bed (and switches itself off after a certain time. "Limits", as the host says...). There is a strong fan, which may be sufficient for you to sleep in the summer, but just be aware that there is no AC for the bed itself. My partner, who cannot use fans, slept on the sofa instead.
Obviously a loft is high up, but do be aware there are a good three flights of steps up, before you arrive. Legs may hurt after long days walking around the Vatican!
Shared bathroom is more to the middle of the flat, the other side of the host's bedroom, therefore the loft extension is not quite so 'totally private' once you need to use the bathroom. Kitchen use not included, so my partner went to a cafe each morning for coffee.
These things are worth you knowing, as they were not clear to me from the profile.
What is true is that the space is beautifully designed, with a very cool style. The living room area is spacious and very clean. Francesco was very cheerful and helpful with recommending local restaurants like Taverna Romana, and he lent us a Rome guidebook. He was always available to offer help and advice. Sadly he was too busy to hang out this particular week. He was patient to receive us after a delayed train arrival, and also let us keep our bags in his place on the last day after check-out, while we went to visit the Colosseum. He did allow my partner four ice-cubes for his sparkling water too. The cats are cute, but on a restricted regime as to where they are allowed to be.
Thank you Francesco for all your efforts.