Carla's place is in a great location walking distance to many attractions, very good restaurants (checkout Osteria da Fortunata just down the street), and plenty of shopping (including the daily market down the street). Bus stops are just a short walk from the apartment if you want to get a little further too.
The apartment is well equipped for longer stays with items to cook and a washing machine. Though the wifi only worked near the bed area for me and my mobile service didn't go much further. So setting up a work station at the big table wouldn't be very useful, though there is a small desk in the bedroom area that was in range of the wifi.
I was there in winter so it was a quieter time, but there were still a couple of nights where people out for the night were passing by making a bit of noise. I fully feel this is to be expected, but something I just want to mention for people considering this place but are sensitive to noise.