Beautiful building in great location. Close to Vatican, Navona, Trastevere and more. I had issues with the sofa bed as it was beyond dirty and as I was traveling with my mother I counted on the sofa to sleep in separate beds. I contacted Guido the first night and he responded very quickly he was going to report it. The next afternoon someone came and cleaned under the sofa but not the mattress. So I ended up sleeping in the same bed with my mom both nights.
If you plan to use the sofa bed, let them know in advance! Even if they list it as two-bed apartment.
Other than that it's a nice place.