Anyone else really hope that this is set in Flushing? It's largely Chinese and Korean, there are some mansions there as well as many apartments so whether Marvel wants to make Danny a reclusive billionaire, live in an expensive penthouse apartment or live frugally despite his wealth, he could easily do so.
Plus, putting him in Flushing makes him a neighbor of Spider-Man so if Iron Fist and Spider-Man are both shooting, a quick cameo in Chinatown where Iron Fist and Spider-Man are both grocery shopping at the same store is very, very possible, particularly since they'll be filming in the exact same area. It'll be even better if they both know each other personally in passing but don't know that they're also a superhero, at least until a reveal where it's like, "Wait, you're Spider-Man, Peter." "You're surprised? I always had you on my shortlist of who could be Iron Fist." "I really need to stop the whole, notoriously private billionaire act."
If I remember correctly, Spider-Man is set in Astoria but don't quote me on that. I'd really, really like to see these two wind up knowing each other both personally and as superheroes but not knowing who the other one really is and then have it played for laughs. Especially if Danny is already helping Peter with his bills and Peter doesn't want Danny to find out since something about him sets off his spider sense.