Overall, this was a very good option for a last minute booking for a long weekend in Athens. I would recommend, however consider a few things.
This flat is basic: the decoration is sparse, the cooker is a plug in countertop one, there isn't a proper shower (showerhead, no holder), small TV.
Look into the area where the flat is. Exarchia is a very lively neighbourhood, but perhaps a little bit too lively for some... If you do not like a police presence and the occasional political protest, this is not the place for you. Although, if you like cool bars, alternative culture, and a busy street scene this is perfect. We were a group around the age of 21 and though it was great.