Our stay in Guido's flat was exactly what we expected, the communication with him was really smooth.
The apartment looks just like the photos and the location is in the heart of Rome- not the most pleasant area but close to all the attractions (few meters from Fontana di Trevi) and metro/bus-. Although the building is located in a busy street, the windows of the flat are turned to the intern patio, what makes the apartment really silent.
The only bad point of this apartment is the bathroom (is ok, but is a really cold room and the water takes few minutes to heat)....
I recommend Guido's place it's a fair price for what delivers.