Originally Posted by
travelmad478
Also be aware that renting cars at airports is always more expensive than renting them from city locations.
Originally Posted by
guv1976
Often, but not always.
I'd suggest that the OP check rates from both (along with any association/organization discounts available to him) before actually booking.

I've flown with my family into NYC, used the subway, stayed in Midtown. Having later then picked up at an Avis location in Midtown and drove only down to downtown Philly and dropping the car/van off there, costs of car rentals out of Manhattan are not cheap with all of the taxes and fees imposed. With older age kids/young adults and flexibility in travel, renting back out at either one of the NYC airports or outside the NYC area may be a better deal.
David