I’d wait until you come to NYC before investing any money in this. The Citibike bike share program has very good coverage and you may find yourself using your dahon much less than you thought. Member ship is only ~$180 a year or so, so about the cost of a tune up or some repairs. Also the bikes are heavy tanks so they are great for challenging excercise!
Also, are those 16” wheels? There are potholes here that will literally eat that bike. I do see lots of people on small wheeled bikes like bromptons but in my opinion 20” is the smallest you should go.