We really enjoyed staying in Jimmy's place. The apartment is just like the pictures - on the small side but great for two people IMO. The best part was the location, a block away from Trevi Fountain. Everywhere in Rome we wanted to see was within a 30 minute walk - usually closer to 15 for all except the Vatican. The apartment itself was up two flights of stairs and the bed is a loft so it may not be ideal if you're elderly/disabled. We didn't mind at all given the location and everything else. The towels and sheets were freshly laundered, Wifi and AC worked well (aside from some issues with the remote not wanting to work - maybe battery dying?). Overall it was a good affordable place to stay right in the center of Rome. This is definitely a good area to be with lots going on day and night. Personal tip - walk to Pasta Imperiale on your way to the Vatican for some affordable local pasta from a hole in the wall place.
We also used the airport transportation offered by Jimmy in his listing, which was excellent. Our driver even brought us to one last stop in Travestere(sp?) On our way out of time. It was in a comfortable Mercedes E350 and very professional. It's cheaper than an Uber or most taxis so if you don't feel like navigating the public transport with luggage I would recommend this.
There was one main downside - the noise. The normal noise from people milling about on the street was no big deal but there was frequently LOUD motorcycles going by which venerated between the buildings.. upstairs were running kids and a crying baby at 8 AM, and construction next door added to the noise. The windows help some but there is no way to deaden all that noise. Some of this is just how central Rome is - I don't think they have heard of noise ordinances there.
Also the water heater requires you to leave on the lights in the bathroom, which heat up the apartment - especially while you are out or at night with the windows closed. I'd recommend switching these to LED to get around this problem. Also the water heater itself was not very high capacity - we had to make sure to space out our 2 showers a little bit or the second person would run out of hot water.
These few negatives were nothing compared to the positives though. Overall 7/10, we would stay there again especially given that it was affordable, clean and in a great location.