Pros: the terrace is indeed lovely and the view of the Acropolis is fantastic. Overall the flat is quite clean. The host is very nice and polite, and responds to messages quickly. The area is central and there are a lot of tavernas nearby.
Cons: the area is quite patchy - some streets, including the small street the entrance is in, are a tad dodgy and covered with graffiti. Most importantly, the interior is quite different from the pictures (some furniture, curtains, layout).
We decided to move out after 1 night, and Konstantinos was very nice in all our communication, he responded quickly, addressed our concerns, and we've reached an amicable agreement.