We loved our time at Kostas' place, the terrace is the highlight and sitting in the hot tub at sunset overlooking the caldera is something we will never forget. We had great communication with the host and really nice breakfast provided each morning. Its in a fantastic location right at the heart of Oia and surrounded by great restaurants and shopping. Only downside is the humidity inside the room which meant we had to keep the windows open all the time, although I presume this is natural when being in a cave house.