Apartment is conveniently located very close to the train station, including the airport bus, and walkable to the lively and young Centro Historico neighborhood. Great balcony, with a view of Vesuvius and the city. Apartment has all the basics. It does get street noise, and nights can be a little loud, given its location.
Like nearly every Airbnb we stayed at in Greece and Italy on this trip (9 out of 10 places), you have to communicate and commit to an arrival time, and changing on the fly can be difficult. Having your international data on is pretty essential. Similarly, if you plan to use the sofa bed, we recommend mentioning that in advance so they provide the appropriate bedding.
However, they were very flexible about check-in time and dropping off our bags early (on our second stay here), which was very nice and helped us out a lot!