Nicolo is an amazing and extremely welcoming host. He let us check in early and leave our luggage at the apartment while it was being cleaned, so that we can go explore Rome as soon as possible. He also responds to every text almost right away and is eager to help.
As for the apartment, it is truly a great place, very spacious, clean and cozy. It is also very quiet inside, despite it being close to the main road, so that was a pleasant surprise. Beds in the bedrooms are big and comfy, there is also air conditioning. The only (very little) flaw of the apartment are the showers - there are rain showers, there are no regular shower heads at all, which is a little bit unhandy.
There are grocery shops and supermarkets nearby, as well as cafes, restaurants, bus and metro stations. Vatican city is within walking distance.
All in all I would definitely reccommend staying in Nicolo's apartment, as it is almost perfect with a perfect host.