Wonderful!
First of all, Apostolos was great. He solved every problem we had (he bought a baby's bed for my 10 mo girl) and was available whenever we needed him (even left us a local phone). He is just a great guy.
Secondly, the house is magical just as described. You enter through a maze of old houses until you reach this round old building in the middle of the neighbourhood. We really enjoyed the fact that it was in the middle of a local neighbourhood and not a tourist area, it felt like part of the culture.
The apartment is small but specious and had all the necessities (even a coffee machine). Also it was clean and newly decorated.
We enjoyed our stay.