We normally park at Avistar but I called them and they are full week of April 8 (spring break here in NY).

A couple of other places (AirPark and Dollar Rental) indicate availability and will provide reservations but now I'm worried that they won't honor them (overbook ...)

A reverse auction (priceline type site) airportparkingreservations.com does show availability at both Airpark AND Avistar - they actually charge your card for one night which I find more reassuring - if they've charged you, it would seem more likely they'd honor the reservation.

But I do wonder how the Avistar rep in person can say no availability, whereas this third party site will take a booking. (It does show another place, the Clarion hotel, as being full.)

Any advice?!!