where to leave my car outside NYC
 

As part of an east coast trip, my family and I are driving up from Cape May area to NYC for the weekend. I'd really rather not drive in the city, based on being a pedestrian there, but I'd like to stay in Manhattan. Is there a place we can catch a train into the city and leave our car parked for the two nights we will be there? We're driving back to Philly for car return, flight home. Any suggestions gratefully appreciated.

Have a look at the New York Waterways website.

We drive in all the time. It's not as daunting as you think, compared to the inconvenience of parking outside the city.

The Travel Inn has free parking, and other hotels offer low rates ($10/night), or you can minimize parking expense by self-parking your vehicle in the same garage the hotel uses rather than using the valet, or check Iconparking.com for better rates within a reasonable walk/distance.

Totally agree with djkbooks. The inconvenience of parking outside the city and having to drag luggage on a train or bus just to avoid a brief drive in and out is not worth the trouble. But if you insist, the idea of parking at one of the New Jersey ferry terminals and taking a ferry across the Hudson is not a terrible idea.
http://nywaterway.com/ferry/map/

One option to consider is getting rid of the car once you hit NYC (all the majors have offices in Manhattan) and using the train to get to Philadelphia.

We've done the Ferry route before, and it was fairly convenient provided you don't have gobs of luggage.

Another option is to leave the car at the Philly airport and take the tran into NY from there . . depending on the amount of luggagy you are willing to schlep . .

djk are you sure you can leave your car overnight at the waterway parking lot?

You might want to double check that.

Another option is parking in Hoboken. There is a Little Man garage on 12th and Hudson within the Shipyard Complex. Then the ferry is right there as well as the bus.

Parking depends on the Terminal. Some have no parking, some daily only, some overnight.