The first thing to say about this listing is that Ioanna's an amazing host; really considerate, kind, enthusiastic about your visit to Greece and a great communicator!
The apartment is wonderful, very conveniently located near Karameiko metro station which makes getting about very easy and the view is lovely. It has everything you need for a great stay as well.
As some other guests have noted, the noise from the surrounding bars and clubs can be quite intense, especially on the weekends. This seems to be an ongoing problem in some Athens neighbourhoods and would be true (I imagine) or any listing in this area. I'd definitely recommend it if you're in town to party, are a sound sleeper or happy to bring some heavy duty ear plugs, but light sleepers and early risers might find it a bit tricky to relax.