This was a very comfortable and convenient apartment. It was on the (fifth?) floor of a secure apartment building. There is an elevator which was great for moving luggage and for anyone with a problem with stairs. There was air conditioning, though it needed to be used with care alongside other appliances due to the load on the electricity. The easy solution, turn off the air and run the clothes washer and the dishwasher when you are out and about. There were also heavy curtains to keep out the light and keep things cool. The bedrooms are comfortable and quiet, the baths large and modern. We had five persons and one used the sofa bed in the living room, also comfortable. The kitchen was very well equipped, though we used it primarily for breakfast as the restaurants in Rome are great, including several nearby. There is a separate dining room and a large terrace. We spent a lot of time on the terrace in the evenings.
The location was great. It is very near a metro stop and we used the metro to travel in from the airport, and to get out to sites in the City. St. Peter's and the Vatican Museum are only a couple minutes walk. The Castel St. Angelo, Tiber River bridges, and the old neighborhoods around the Piazza Navonne are also an easy walk. There were lots of nearby restaurants, markets, and a pharmacy.
Check-in was a bit slow. We had to wait about fifteen minutes at the door. The host tries very hard to coordinate your time of arrival, as they must meet you and escort you up for check -in. At check-in we were given instructions on the elevator, the air, the kitchen, and care for the terrace, and offered transport to the airport for our departure, which we did coordinate.
We communicated with the host through the VRBO site prior to the trip, and through WhatsApp after our arrival. They were always responsive, though sometimes a bit slow. They manage a lot of apartments, so it helps to advise in the WhatsApp communications your name and location.
I would very much recommend this unit to anyone visiting Rome, and especially to anyone whose visit includes the Vatican.