The appartment from Simone and Susanna was even better than expected! It is very comfortable, high quality and just everything you need. Two bathrooms, three bedrooms (and a living room with a couch which you can transform to another two-persons bed) and a nice balcony to eat. Metro station in less than 50 mtrs walking distance.
Also Simone and Susanne were very friendly before and at our arrival. They arranged a taxi from the airport to the appartment and took the time when we arrived. They have a few nice self-made tourist guides with local tips to enjoy your stay in Rome even more! Great people, very helpful if necessary.
If I may add one thing to improve, it would be one of the beds. The mattress is quite hard.