I think that Domus Giulio Cesare is by far the best AirBnb I've ever stayed in.
The location is great, 100 meters away from the Lepanto metro station, and you can walk anywhere downtown if you are willing and have good shoes —we only took the metro to Termini—.
The place is clean, it smells fresh once you come in, everything seems new or is very well kept. It has all the commodities of a hotel for the price of a BnB. There were fresh towels and a hair dryer, they even made our beds from one night to the next!
In fact, the photos don't do it justice since the rooms are larger and brighter than I had imagined.
Thank you for having us, Lorenzo.