Federico’s apartment is very conveniently located to explore Rome. Roma S. Pietro is the closest (within 5 minutes walking distance) railway station, and there are about two Metro stations within 15-20 minutes walk. If coming via Roma Termini to Roma S. Pietro, on all the occasions we had to do this, the train pulled in to platforms 25-29 at Roma Termini, which is quite some walking from all the other platforms. I am writing this so others can be aware of this when planning the visit. Regarding distances, the Vatican is quite literally next door (say 15 minutes walk).
The apartment itself was as expected. Clean, a goid sized sofa bed (my two teenage sons shared it without a problem), and a big bed in the bedroom. Ample storage spaces if you plan to spread out your belongings and make yourself comfortable. All cooking utensils and crockery and cutlery provided. Not only that, Federico allows the guests to use dry and un-perishable food left behind by others. If you are so minded, a nice big TV is also available.
As for Federico, what a gentleman host he is. We were late checking in due to train delays, but Federico was very patiently waiting for us. When we had a problem closing the kitchen window, he came in to help us and show how it’s done (simply a bit more force than usual was needed). Good, convenient place to stay in Rome.