I have several caves here, and at one time had planned to live in a huge rock shelter, open at both ends, but was denied permission by the Archaeology Department due to some prehistoric bones and stone tools found in one area of it. I've also considered one as a "bunker" shelter in case of CME or other radiation event needing long term protection, so have given it a lot of thought. The main problem here is the humidity... a dry climate might make it more comfortable to live in a cave, but a humid climate would not be pleasant to live in long term. Think dripping stalactites all over the ceiling. There is also the cold factor, 20 degrees or more below the ambient temperature, sharing with bats, the perpetual darkness and limited access. In the man-made caves those problems might be overcome easier, but natural caves don't have human comfort in mind as they are evolving. In some ways I think they are fragile as well, and would have major damage with any kind of earthquake or flooding, both possible in this geological area. It's the same with real estate wherever you go... location, location, location.