We LOVED staying at Nikolas's place. We stayed here for the first four days of our honeymoon in Santorini. Pori beach is about 15-20 minutes from Fira and Oia, so you'll need a scooter or ATV, but we loved staying a bit removed from the other tourists. I was worried it might be a little too "rustic," having read some of the other reviews (I can be a bit high-maintenance--I hate bugs and getting dirty). But that wasn't a problem at all!
In the Selana, you wake up every morning to a view of the ocean through your window. The living room is large and breezy, with a gorgeous view of the ocean as well. The rest of the house is beautiful and clean--lots of natural wood and light, everything clearly hand-made with love. I wish we could have stayed a few more weeks! There are even seats in the front and back of the house. In front, you have an ocean view; in the back, a view of the mountains. The house gets hot during the summer, and the windows don't have screens, but Nikolas provided a fan, and as far as I could tell,we didn't get bugs in the house when we opened the windows. Side note: we saw a lot of geckos, both outside and inside the house, but that's everywhere on the island, including the other place we stayed at in Oia.
Finally, Nikolas is a wonderful host. On our last day, we were going to take a taxi into Oia to catch our bus, but he offered to drive us there instead. He's a warm, gentle person who carries an atmosphere of peace wherever he goes, and it was an honor to meet him. I highly recommend staying here!