Leo's place is situated very conveniently in the heart of Trastavere, but on a private side street so it's still very quiet. It's just steps away from plenty of bars and restaurants and just a few minute walk to the Piazza di Santa Maria. It is about a 15-20 minute walk to sites like Piazza Navona and a little over 30 minutes walk to the Colosseum, so it might not be the most convenient if your focus is on some of these historical sites. Public transportation on the buses is very convenient to get around town.
Leo was an excellent host. She greeted us upon arrival and check in was very easy. She provided a fully stocked fridge with water, juice, yogurt, and even a welcome bottle of prosecco. She was very easy to communicate with and responded very promptly to messages.
The unit is cozy and great for two people. We slept on the pull out sofa bed, which was comfortable enough considering it is a pull out sofa bed. There is a mattress on the loft above the bathroom, but it's close enough to the ceiling that you might hit your head if you do you not sit up carefully and getting up and down the ladder is fairly precarious. The unit is fully stocked with an espresso machine, kitchenette, washing machine, air drying rack for clothing, private patio, and well functioning wall AC unit.
As other reviewers have mentioned, the wifi is very spotty and there is no cell service inside of the unit. You can get some cell service if I you sit outside on the patio, but that's not ideal during peak summer or winter days due to seasonal limitations (summer heat or the mosquitos at dusk/night). Wifi is through a 4G/LTE pocket wifi device charging in a closet off of the patio. We were able to get a little better wifi connection by putting the pocket wifi device inside the unit near the windows of french door entry to the backyard patio and plugging the device into a portable battery charger (there is no wall outlet near the patio back door to plug it into).
Leo was a great host and the location is perfect for access to Trastavere and public transit for getting around the city. If these are your priorities, then I would definitely recommend this place to stay.