Newark Liberty International Airport Parking Economy Parking Lot P6 is not currently accepting reservations on AirportParkingReservations.com
This lot is convenient as it is located on-site with easy access to the terminals via the shuttle. It's a bit pricey when compared to off-site lots that offer the same convenient service.
The price is cheaper than other 'on-airport parking' locations for EWR, however, this lot is pretty far away from the terminals. I had no issues when I parked here, but you will probably have quicker commutes to the terminal, as well as cheaper prices, with other lots that are off-airport.