what can I do to get the past due rent from tenant? New York city (accept, house)

[Stacy-7]

It is a house in New York city.
Lease expire and tenant is not paying rent. Starting a holdover case.
I know when a holdover case start LL can not accept rent from tenant but tenant owe rent for 2 months, next court day is next month. Eventually tenant get evict that will take atleast 3 months.
Tenant has good income and good credit. Can I contact collecting agency to collect rent? Or will I need court paper to do that? Or anyother way to do so.

Thanks everyone.