We really enjoyed our stay in this apartment both because it is very nice and spacious, and also because Claudio is a very attentive host and he took great care of us and of our needs. He gave us great tips about the city and what to do and what to avoid, and he picked us up from the airport and brought us back when we were leaving. This was a paid service, but it was the same as the taxi, and it was nicer because we could talk on the way. He also kept us informed about important events such as the football game which influenced the public transport system, so it was good to know this ahead.
The apartment itself is just a few steps from the Vatican City walls so it was very practical for the Vatican sightseeing. We walked everywhere, even to the Pantheon (about 30 min walk) and to to the Trevi Fountain. We took a taxi (IT Taxi - recommended by Claudio) to the Galeria Borghese and metro to the Colosseum.
The apartment itself is in a nice, very clean building, with a nice garden and a nice view. The street outside was busy, but this is Rome and I don't think you will find a quiet place in such central location. The apartment has a small kitchen which enabled us to have an unhurried breakfast each morning. You will find all the basic necessities in the apartment: air-conditioning, iron and ironing board, washing machine, two good hair dryers (I recommend the black one), a kettle etc. You will be comfortable here :-) Enjoy Rome!