We loved our stay at Kal's! Kal himself was super nice and communicative (we didn't meet in person). With his detailed instructions we were able to get to the apartment easily via public transportation directly from the airport. Check-in was easy (his lovely sister was there to welcome us), the apartment was clean and comfortable. We didn't find anything missing. We thought the apartment was conveniently located even though it was a bit out of the way from the "nightlife" which seemed to concentrate near the subway station (within walking distance). We'd definitely recommend and stay again if we make it back to Greece!
Thanks Kal!