I stayed Federico's flat for 5days, and there were some pros and cons I felt.
Pros
Location
The flat is really close to Termini station. You can reach to several public transport stations by walk so it is good for exploring around the city.
Well-equipped and homey
The flat is large and quite well-equipped. I especially liked the kitchen. I could use a couple of pots for cooking. The sofa and bed were really comfortable as well.
Also the place is well-decorated, you can feel great taste of the host. It was a lovely and homey place.
Cons
Very hot in summer
You have to know that summer in Rome is really really hot. In his flat, there was no A/C as he mentioned(it is totally usual in Rome). Instead of A/C, there was an old fan and it was not functional well... The wind was weak and it was extremely noisy so I couldn't sleep well with this. If you are thinking about traveling Rome in summer, I'd like to recommend you to reconsider this apartment.
Neighborhood
During I stayed his apartment, I could recognize that it was not a local area. I couldn't find Italian restaurants in 15mins walk distance😂 The street was dirty and I could see some homeless guys as well(Maybe because of Termini station). If you are a female traveler, I would't recommend this area.
Noise
It was a bit noisy in the midnight because of trash collecting cars. There were a few of big trash bins right in front of the apartment. So trash collecting cars came and took the trash at 2am...... it was a bit annoying for me.