This place is stunning! We very much enjoyed our stay and were sad to leave. The location is perfect - right in Oia, but far enough away from the main road to feel private. As other reviews mention, if you strongly prefer a private terrace, this place is not for you. You do have a little nook that is yours, but you share with 2 other neighbors which we didn't mind at all. The house next to ours was a nice French family, and the far end neighbors are 2 French teachers that come to the island every summer - they were very sweet and we ended up sharing several drinks on the terrace. The interior is very nicely decorated and you have everything you need. It did get a bit warm at nights, but the fans helped.
Santorini is full of tourists and we happened to be there at the busiest time, but were able to avoid them for the most part thanks to a local friend. There is so much to explore on the island so I'd highly recommend renting a small smart car. Also, if you aren't in shape or have trouble walking up and down stairs, you may want to arrange help bring in and out your luggage as it's a bit of a walk. We didn't mind and were thankful for this though as you don't deal with the crowds.
Andromachi was available and responded quickly, though we honestly didn't need anything during our stay. We'd definitely recommend this place to everyone and look forward to returning!