Federico's place is fab! Spacious, clean and bright room, good facilities such as bathroom (with bath), kitchen and washing-machine. Even a private balcony.
The location is great too being in the middle of Trastevere which is a lively & colourful neighbourhood with many restaurants, shops, galleries and attractions of its own.
Additionally, it's close to the city centre plus the ancient part of Rome and not too far from the Vatican. I was able to walk to most places of interest in 1/2 hour.
I should mention that the flat is vintage in style (which I personally like) so maybe not best suited to those seeking a modern place. But the price is very reasonable .
Last, unfortunately I got pickpocketed and Federico was very kind to lend me money and let me stay longer to replace my passport. I recommend having valuables (money, credit cards, passport) in a pouch hung round the neck rather than trouser pockets (even front pockets) as crime seems an issue here (specially at the tourist sites and Termini Station) and there are many pickpockets & hustlers. But with precautions, Rome is still an amazing place.