Short-term rentals are largely illegal in NYC.

While actual short-term apartment rentals in NYC are illegal, there may still be some options in apartment-style hotels, which do exist, though I think the idea that you will find any 3-bedroom apartment in the entirety of NYC for much under $1000 per night is highly unlikely.

Such large apartments just don't exist for the most part in NYC except in public housing projects and multi-million-dollar luxury condo buildings.

I do think you might be able to find a 2-bedroom and a 1-bedroom in the same building, but again you need to focus on apartment-style hotels like the Affinia properties, the Beacon, Radio City Apartments, etc. You'll find very few options even in the 2-bedroom range. But I'd urge you to book something soon. Eastgate Tower, for example, does have some two-bedroom units, but they won't allow 7 people do occupy them, even if 3 are children.

This is a really BAD idea.

Not only is it illegal - and the subletter's neighbors may well report you to the city, which is cracking down on this infraction - but there is a significant chance that the rental may be a scam.

Absolutely look at suites in hotels that are converted apartment houses (and thus following the law in terms of number of occupants, safety and taxation).

Look at VRBO and AirBNB.

Nelsonian, although I have used vrbo in many places, it is a really BAD idea in NYC. They don't vet their listings for being legal.

We stayed in a VRBO apartment in Long Island City, don't know if it was legal or not. It was perfect for us, close to subway, and our daughter.

The apartment in Long Island City was in all likelihood not legal. These things are all fine if everything goes according to plan, but if not, then you are stuck with no legal recourse (since you are breaking the law) and the necessity to find a replacement hotel at the last minute at what is usually an exorbitant cost.

The article in the times pointed out the potential risk - large fines and loss of lease - of the origianl renter of the apartment. If you are staying in one illegally and there is a complaint from a neighbor, super or doorman - you can be removed as trespassers - since you have no legal right to be there.

(And this has happened - the City shut down an illegal hostel - removing all of the tenants late at night and leaving them to find other lodging. It's not common, but it can happen. Never ind those that are scams. If you have a high risk threshold - go ahead - but it's not a chance I would like to take in finding lodging on the spot in NYC.)

Looking at sites like VRBO, AirBnB etc., does not mean that the leasing company is trustworthy, or that the apartment in New York is being legitimately let.

We learned the hard way through dealing with a company called Vacation on Vacation. The property listing was misleading in terms of location, there were problems while we were at the property, and getting the deposit back was a struggle.

Seems like our experience was typical, and since returning we discovered there is a website sharing similar experiences about this outfit - vacationonvacation.info

This apt. is legal because it's a small building with the owners living on the premises. http://www.vrbo.com/138897

The Marmara is an apartment hotel that has some 3 bedroom 3 bathroom suites. I think you might want to compare the costs against splitting up in 2 rooms elsewhere though.