I seen one for like $500 and just assumed there could be some for 400

I did, I couldn't find any in the price range I was looking for.

I don't even live in New York so I wouldn't know the average price of an apartment is there

Like everyone else said, you aren't finding anything within a 60 miles of midtown Manhattan for $400 a month.

If you want a real estate listing, then go to a real estate site, like zillow, apartments.com, or google 'apartments in New York City' and see what comes up. Did you seriously think that someone reading this was going to have a current list of all the apartments in NYC, or did you just expect someone do do all of the work of looking them up for you and then posting them here?

ROTFLMAO !

A $400 a month apartment anywhere in or near New York City ? No problem, just take a time machine back to 1960.

In 1994, my now ex wife got an illegal basement apartment in Nassau County, which had a kitchenette, one actual room, and a bathroom. One of the things that made it illegal was that the only window was in the entry door, so if there had been a fire, one that blocked the door, there would be no other way out.

And, the rent was $650 a month... in 1994. And, NOT in any of the five boroughs of New York City.

You have NO clue.