Lovely apartment on a great location. Centro Storico is 30min walk, Trevi is 10min walk. Walk up the road and in 10min you're at the top of Spanish Steps, where there's a metro station that's open (piazza Barberini metro is closed). Metro can take you to nearly all other areas, including Colosseo, Vatican/Prati, Testaccio, etc.
Windows are double-glazed, but no rubbers for sound-proofing, so you'll hear traffic and in the evenings of the weekend you'll hear the street noise than you can expect in such a central location. Traffic is quiet in the night. We had no problems with the sounds.
We were really happy that Luca was kind enough to provide a baby cot, so we didn't have to use our smaller travel cot. We had to adjust some furniture to place the baby cot and found the floors under the furniture to be a little dusty, but otherwise clean.
Kitchen and bathroom have all necessities, and all necessary amenities were provided. Note: bathroom includes both bath and shower. Apartment had higher ceilings than expected from the photos (I could stand straight everywhere at > 1m90, except for the wooden beam between bed and bathroom).
In summary, great apartment, excellent location and a wonderful stay. Would recommend.