Highly recommended! Lorenzo very helpful, mattresses comfortable (American queen size), great location, very quiet, very clean, , close to transportation, nice views. Lorenzo was super helpful: always quick to respond and he arranged for a van taxi to pick up the 4 of us at the airport and was in contact with driver to make sure we arrived at the door where Lorenzo met us. Well worth the 55€ (set price of 45€ From airport to downtown plus 10€ to call or book ahead). As others have noted, Lorenzo helped carry our bags up the stairs. We thought we were just leaving our bags but housekeeping was just finishing so we were able to check in early which was so wonderful after our overnight flight. Flat was very, very clean, kitchen very functional for making breakfast - under counter size fridge was good (we didn't cook). Mattresses were firm with cushioning. Great location: we walked 5 min to the Roman Forum etc., along the river, and theough the pedestrian area across Trastavere. Very convenient to major bus lines and taxi stand. Numerous small restaurants very close by in small piazzas and streets on our eastern quieter side of the Trastavere. Mini marts and other shops close by (there was a fabulous shop with takeaway bread, pizza and salad items a few blocks away from the river in Trastavere on the west side of he street.) Quiet and with the double glazing we didn't hear a thing. Windows opened wide out onto a pleasant side street view. We used the airconditioning at night which was beautifully quiet. Wifi worked great and we borrowed an adaptor plug to recharge our devices.
There was a slight musty smell when the windows had been closed but once aired out it was only noticeable under the kitchen sink: think this is part of being in an older building with character which we very much wanted!