I've seen balcony rooms available on the Grand for $661 if you're into that kind of thing.
Last cruise I had a balcony and I'm not sure I could live with an inside room anymore. It all depends on your tastes though. I really enjoy sitting on my balcony reading a book as the waves go by. Others want to do all the shipboard activities.
Though the airline bit is probably going to be your biggest problem when it comes to last minute travel, airfare will more than likely eat up any savings you might have gotten unless you live near the port and take a cruise. You'll still probably have to pay $50-$70 for parking though...