Maria was very kind, because of a strike we couldn't get to Sifnos and she kindly cancelled one night. She was very flexible regarding the check in. Kostas waited for us and gave us great recommendations, we had some wonderful days in Sifnos, also thanks to his recommendations. Maria's apt is small, but you'll find everything you need. Kastro is also a nice place to live on the island, it's very traditional and quiet. We highly recommend Maria's apt!