You also have to take into account that the cruise lines want information weeks beforehand, so you can be investigated thoroughly. Waiting until a week beforehand will probably give enough time for clearance. There are many good values out there, especially the Caribbean in August, as this is hurricane season, and a lot won't take the risk. If you're willing to risk it, the deals are there. I just saw a week in the Caribbean starting at $269/person. How can you not afford to take that risk?