My sister and I spent a week at Paola's place and it was fabulous. Previous reviews have mentioned both the wonderful terrace and large amount of stairs and I can only agree; the terrace makes the long slog up the stairs worthwhile.
The location of the building was also great - it's right in the centre and we felt like Neopolitans for a week.
My sister arrived first and said that Paola was very helpful and gave her a detailed tour of the flat and pointed out the sights of Naples from the terrace (you can see pretty much everything!) Unfortunately, I didn't have the chance to meet Paola, but she replied to every message quickly and was really helpful.