Matina was incredibly kind: she picked us up at the port the day of arrival and rode us back the day of our leaving.
She gave us helpful information about the island and helped us with anything she could.

The house is in a breathtaking spot: the view is amazing especially at the sunset and the place is incredibly quiet. On the one hand, it's into the wild (friendly cats, dogs and chickens all around and in the morning the alarm clock is the rooster - sometimes it can be annoying, but that's the way the nature works :-) ), but on the other hand, it's very close to Mericas (5 mins by car/motorscooter and 20 minutes walking: we did it once on foot to digest the dinner, and it took exactly 20 mins).

Seeing other comments, my recommendation is: if you don't like the nature, don't go there (maybe don't go to Kythnos, as it's a wild island offering wild nature more than nightclubs); but if you do, it's definitely the perfect spot!