Is about 15 minute walk (slightly downhill) from Roma Termini station (look out for the bus station side - Piazza dei Cinquecento as it is a large station with multiple exits). You can get a metro train from the train station to Via Cavour station but hardly worth it.
Check in was straight forward as one of team were waiting there at the agreed time.
They did helpfully share the Metro line closure schedule during August which allowed us to plan accordingly for our Vatican visit.
There is a single set of slightly winding steps to the apartment on the first floor.
There were air conditioning units in the bedrooms and living room and they worked fine. A single but spacious bathroom with good shower and twin sinks. The kitchen had the usual equipment and utensils. There isn't a washing machine which I was aware when booking so did a full wash at our prior AirBnB and Rome was our final stop so was not an issue (also there is a laundry next door which looked popular). I hadn't registered there was no microwave and didn't personally miss that but something to note if you would need one.
There is a Coop supermarket up the road about 5 minutes away which we used for our essential groceries. The Elite supermarket down the road was more for the specialized products and deli. The American supermarket was closed for holidays.
Via Cavour is like many of the roads in the area pretty busy with traffic from early morning so anyone who is very sensitive to noise and wants a lie in needs to bare that in mind. It is good location for getting down to the Coliseum, Roman forum and then beyond. There are lots of different restaurants on Via Cavour. They cater for the tourists particularly as there are lots of large hotels and the couple we tried were fine after a day of sightseeing but nothing special.
Checkout was easy as we left the keys in the apartment.