This place is phenomenal! It is literally above the la fontaine de trevi which is sometimes a little noisy. Remember that from 5 am to about 2 am the fountain is packed, completely full and about 15 times a day, someone proposes matrimony to their girlfriend so everyone in the fountain screams and applauds.
Also, it is in the 5th floor and no elevators. With that said, those two minor things do not downgrade it from being excellent. Great location close to restaurants, bars, and all the important, touristy landmarks (walking distance). About the owner Filippo! This guy goes above and beyond what is expected from an owner. He lives across the apartment so anything you need, he is there within seconds. He tries to help in whatever he can whenever he can. I think Filippo makes this place a highly recommended place to stay in Rome. One very important things i have to say (not about the apartment) is that whenever you leave the apartment and you are going to buy food, beer, drinks, ask for the price first because everyone there price gouges. It happened to me in a restaurant ANTICA FONTANA DI TREVI in front of the apartment. I looked at their wine list and not one over 30 euros so i asked for a Moscado (9 euro bottle at a local store) and since it was not on the list, they charged me $70. At this restaurant, the make a habit of cooking you "whatever you want" so items will not be in the menu and at the end........BOOM.....they scam you! DO NOT go to this restaurant.....remember the name ANTICA FONTANA DI TREVI in front of the apartment to the left.
About the apartment........excellent and highly recommended (good exercise too)!