Our stay at Nicola's place was excellent. It was my wife and I, and my parents. There was plenty of room and privacy, and the location on the first floor was perfect - not many steps after long days of sight-seeing. The flat was very well located, there were many restaurants and shopping nearby, and two food markets that were very close. It was within walking distance of the Vatican and some other monuments, although we ended up taking Uber/cabs for most excursions.
Nicola was very helpful and friendly during check in, offering some local dining tips, and telling us a little about the place. He also arranged our airport transfers, and was very quick in responding and communicating.
This was a great place that helped make our visit to Rome a fabulous journey!