I stayed at Federico's when I first arrived in Rome and decided to stay at his place again before I leave Italy. His place is in a good location and easy to commute to anywhere; 15 mins to Colosseum by foot (only 2 bus stops) 2 mins walk to metro and bus station is right next to each other. It is also close to Roma Termini (train station) Federico was very helpful and easy when checked in. The place is very clean and spacious. The only downside was that wifi didn't work well, maybe only while I was there I am not sure. But highly recommended for a solo traveler or couple or even small group of 4 as he has 2 rooms. Although sharing a bathroom but it was never a hassle. Would love to stay at his place again when I am back in Rome!