Location, location, location. Francesco’s place was perfectly located near Piazzo Navona, and within walking distance of Vatican City. Dozens of great restaurants and shopping were with less than a couple 100 meters of the front door.
However, this 15th century apartment could stand a little updating. Things like the shower head spraying water all over the bathroom and a bed that was the inspiration for the rack were disappointing. But the worst was every time you used the bathroom a foul smell (gas?) came out of the sink and shower drain.
Lastly, the four flights of steps may not sound daunting, but with suitcases in high heat and humidity it isn't appealing.
Overall, the location of Francesco’s apartment was fantastic. A little maintenance/updating would make it quite appealing. And, it's on the 4th floor. Take it or leave it.