Roberto's apartment is spacious with two terraces on 4. floor. A great thing is that it's very close to Trastevere train station with direlink to e.g. the airport, St Peters Church and the beach (we chose S. Marinella based on Robertos advice - and loved it).
When heading for Trastevere for dinner you need to take bus 8 five or six stops - but it' s not a big issue. For us the sights of Rome and Trastevere was too far to walk. Across the street are great local joints for breakfast. The flee market in Trastevere is just down the street.
When we visited Rome it was 34-37 C., and therefore also hot in the apartment. However the shower is nice and there are two fans in the apartment.
Roberto is very nice and service minded. We recommend staying at his place.