For a five day cruise, it's $70 cash, (they just about pull your fingernails off taking it too). The parking is splendid compared to the old terminal facilities. You drop off luggage, park, and take as elevator to the floor you check-in on. Never in the sometimes rain. It's a breeze.
The $70 you pay for secure parking is cheap for that area. Most other lots, (uncovered I might add), charge $20/day. As for parking at a WM or some other place, I work down there and I wouldn't trust my vehicle on the "streets" for 5 days. There are some "Park and Cruise" hotel/motels in NO, but I'm not up to snuff on the details. When inquiring about accomodations,,,,,ask. I don't think it's that much more, and they do offer packages at some places.