The location of this apartment is excellent! Right in the middle of Trastevere which is a beutiful part of Rome with many restaurants and walking distance to most of the sights (we didn't use any transportation, just walked everywhere).
The host was very friendly and helpful and greeted us and showed us everything although we didn't arrive until midnight.
The double bed was very nice and great with two bathrooms (both shower and bathtub), but the single beds were not that comfortable and too short (180 cm?) for some of us in the group (four friends travelling together). The apartment has a small kitchen and the room with the three single beds has some armchairs. The apartment was very clean.
I'd say it's a great apartment for spending lots of time in Rome with excellent location, but not an apartment to "hang out" in since there is no living room and the kitchen only has a small table. We used it only for sleeping (didn't cook) which worked great for us!