We spent 2 weeks in Greece (mainland & Sifnos), and Konstantinos' apartment was by far our favorite stay. You cannot top waking up to the view and sound of the sea right outside/below your apartment. It's magical. Konstantinos provided great recommendations and was very responsive before our arrival. Voula, the staff person on site during our stay, is delightful. She tidied up our room every day and was accommodating with our requests. Kastro is a beautiful town, and the parking near the apartment was a plus. I can't recommend this place enough!