The blue volcano is a decent place for one - two nights. Just understand what you’re paying for - the view. Which is incredible for sure. I was only there for a single night and don’t think I could’ve stayed any longer.
Nothing wrong with it, the room is just fine... barebones, nothing much in the way of amenities. There was tons of construction in the immediate area around the room which made the stairs to and from the apartment more treacherous than they already are. It is the off-season though and that’s no fault of Maria’s or anyone. I liked the place, I just wasn’t entirely comfortable.
For a quick visit to santorini, the blue volcano is just fine.