I live in the area. Leaving some bits of information here for anyone curious. When you buy a ruin, apparently you might be required to preserve the façade. You can't just demolish the building and build from scratch. Construction is constant, especially in summer, and the construction workers are busy. We're planning a substantial renovation of our house and it's possible that we'll have to book the team a year or more in advance. The supplies and methodologies used in traditional Azorean houses, and, consequently, by local teams, might raise some eyebrows. For example, it's now several times that different construction workers insisted I should just put new tiles/flooring on top of the old without removal.