Great people, the apartment was exactly as it was described: under the stairs, so you get full protection from the sun (which is really hot in Greece), very clean, good internet, smart tv. Me and my wife just walked, so it's about 10 minutes walk to the first supermarket, 20 minutes to the center if you go straight on the national road (sometimes it feels dangerous), or 25 if you walk on the beach (just follow the Malibu beach road, it's really nice, especially at night). It's not the in the center of Kardamaina, but it's quiet, which was exactly what we were looking for.
Once again the hosts were great, very responsive, friendly and welcoming. Panagiotis mother even took us the airport (efharisto!). You can ask them everything and they will gladly help you. If you go to Kardamaina and not looking for noisy stays, I totally recommend their stay.