I'd like to rate this 3.5 stars but that's not an option.
The good: we loved the location for the cheaper restaurants and coffee shops. We walked everywhere but public transit is so close. Vatican city is 1 hour 15min walk, Colessum is 30 min walk. The apartment was clean and the bed was comfortable. Air conditioning worked well.
The cons: we were greeted not by Massimo but someone else who was smoking in the apartment... My partner has asthma and is allergic to smoke, so this was an issue. (We left the windows open the first night and then it got better). The shower was broken - you had to hold up the head and like it down on the floor again when you shampooed etc. While we liked the area, beware of used needles and syringes, urine, and even human feces on the sidewalk when you walk ( lots of homelessness and drug use in the area, however I never felt unsafe).
I'd definitely recommend the apartment if you aren't sensitive to smoke. The restaurants in the area are AMAZING and the proximity to sites is fantastic.