That’s the in-house slang used by real estate agents (realtors) to describe residential real estate (as opposed to commercial). So we have this, from Britishland:
Centre Point joins growing list of empty luxury skyscrapers as developer gives up trying to sell apartments for up to £55m each after receiving too many ‘detached from reality’ low offers
I would suggest that someone trying to sell a simple apartment for £55 million is the one who’s detached from reality, but then again I’m no market expert. Even Mr. Free Market, who is, has expressed disbelief at some of the prices being asked for places that are, in a word, overpriced even for one of the most expensive cities in the world.
Judging from some of the pictures of said places, they could best be described as “not memorable”.
(Me, I’d call them pig-ugly but that’s because I detest modern architecture and decoration.)