I recommend staying in Sara's apartment.
Coming here in one of the hottest weeks of the summer I was worried about the temperature but the AC of the room worked flawlessly. It even has a programming function so it switches on while you are outside and then you come at night and the room is already at a very comfortable temperature.
The room is very spacious for one person and Sara's assistant had everything prepared for me.
The private bathroom is a great addition for that price and the breakfast snacks are really welcomed.
The location, very close to Termini, is super useful, since it is the only station in Rome where you can access both metro lines. So it doesn't matter if it is a little bit farther from some tourist areas like the Vatican, because you have instant access via metro. And then Termini has lots of trains and buses options to choose from as well.
Overall, a great experience for me.