Antonella's flat is a studio apartment by definition. It's cozy - it's one bed, a kitchenette, and a bathroom. The kitchenette has two electric burners and some items for cooking, but as others noted, space in the kitchen is an issue and I wouldn't recommend cooking elaborate meals.
The room is adjacent to her flat (there's a shared door). The noise level was minimal - this is a room in an apartment complex facing the quad. Due to the proximity, you can sometimes hear phone conversations or people in the other room talking. You'll have to provide your passport information at check in, it'll be provided to the police in case the stay goes awry.
Antonella was helpful, giving us recommendations on where to go and how to take public transit. She provided us a big bottle of sparkling water upon arrival.
Above the bathroom and kitchen, there's a lofted twin bed, which can be useful for accommodating more people. However, I think three people would be a little too cozy - I'd recommend this as a good place for couples.
One inconvenience was the electric motor under the toilet. It would run (and making a pretty loud whining and whirring noise) every time water went down the drain (kitchen sink, shower, flushing the toilet, bathroom sink).
The location was good, close to the Manzoni metro, and about 15-20 minutes from Termini and the Coliseum.
Wifi was fast, and although we didn't use the TV, it was a big 32" LCD, which could use useful for someone with a Chromecast.
Thanks Antonella! We enjoyed our stay.