NYC has RENT CONTROL. Unless he lives in a newly built luxury apartment, his rent cannot go up nearly that fast. And if he does live in a luxury apartment, he can afford the increase.
Read the fine print:
https://en.wikipedia.org/wiki/Rent_control_in_New_York
“To qualify for rent control, a tenant must have been continuously living in an apartment since July 1, 1971, or be a qualifying family member who succeeded to such tenancy.”
NY has 3 levels. Rent Control, Rent Stabilized and Decontroled.
He's probably Decontrolized and landlord raised his rent based on assesment.
It's insane. Just got my assesment. NYC decided what the gross rent income is. I wish it was what they think it is whereas I only receive less than half. Now I have to fight their numbers.