I don’t see anything in the article mentioning the expensive nature of such a thing. Definitely curious on any insight you can share on what makes it such an expensive thing? As someone not knowledgeable on the topic I wouldn’t expect it to be too costly since it already has a decent amount of plumbing, electrical work, elevators, stairs, and an entire building already constructed. Obviously some heavy reno work would be required, but it’s gotta be much more cost effective than building from scratch?