If you are looking for an authentic Greek cave house, with one of the loveliest views in the world, look no further than Rena's Caverne des poètes. While it was more expensive than some of the other locations on Santorini, we decided that it was a once in a lifetime experience, not to be missed. (The same holds true for Santorini.)
Here are the pros:
The view. (Did I mention the view? Imagine sitting on your patio, looking over the cliffs to the sea. Just stunning.) Authentic cave house with air conditioner that works very quickly to cool off the place. Espresso/coffee machine with pods. Small refrigerator. Comfortable beds. (Greek beds are much harder than those here in the U.S.) A wonderfully large bathroom with a shower that you can actually move around in. (Rare to find in Greece--at least in my experience!) Location close to the main shopping area (via a lot of steps) and restaurants in Oia as well as distance to castle to watch sunset.
The cons: (Note that we did not find any of these things detracted from our stay--we would absolutely stay there again. But I feel a renter should know what they are getting into to make an informed decision.) There are a LOT of stairs to get down to the house--possibly 6-7 flights of winding steep and sometimes slippery stairs. I am a fit 60 y.o., and became slightly out of breath going up (and you have to go up to get to anywhere in Oia). Also, if you have knee issues, you may want to reconsider as you must also go down the stairs, and they are steep. My knees (which aren't great) were screaming the last of 3 days. We tended to go up/down at least 3 times a day. The table and chairs inside the house are a children's set--not sure why. I would prefer even a small bistro table of normal height. (There are a couple of director chairs at least.) But I need to work, and there was no table to work at. The patio, where there is a full size table, gets too hot in the afternoon to sit at too long. The bedroom downstairs stays cooler. The stairs are typical steep cave stairs. However, you need to DUCK on your way up or risk smacking your head on the beam. I feel a few pieces of short ribbon tacked to the beam will warn the visitors. (We both smacked our heads once. We learned fast.) Also, be aware that there is a door between this apartment and Rena's other apartment. It is just like a hotel door that would open between suites. And, just like a hotel, conversations can be heard. So mind your Ps &Qs (or sleep in the downstairs bedroom!)
So, again, do not let the cons dissuade you. I only present them so you know. This was a lovely stay in one of the most picturesque villages in the world. The apartment is away from the madding crowd, a welcome respite to the long, Disneyland-like lines of cruise ship visitors who crowd the sidewalks. If you don't mind stairs, you will appreciate the privacy and quiet of Caverne des poètes.