I would highly recommend Kostis' place. It is in a great location in the heart of Oia. the place is more spacious than it appears in photos. We were a group of 6, 3 couples, and we had more than enough space. We spent a lot of time on the balcony as the view is stunning. Their is a large patio as well. Kostis was very accommodating with our check in and arranging transportation for us. Also, when we initially booked the listing did not have air conditioning as an amenity, however their was a unit in the main room which worked great. Overall, this is the best place to have a truly amazing experience in Santorini.