Here's a siren song for the stressed-out traveler: "all-inclusive vacation." Pay all your costs upfront, this seductive sea nymph croons, and whip out your wallet no more.

It's not always a lie. But to avoid scuttling the family budget on faraway shores, figure on extra expenses that can add hundreds to your trip costs. How much depends on the resort or cruise and your idea of fun.

If your passions run to water sports or golf, book a resort that includes these in the package. If kicking back means downing a few drinks each day, go for unlimited alcohol. At tropical resort chains such as SuperClubs, Sandals and Couples Resorts, you may be able to get it all -- almost.