Hotels and resorts are always giving away free nights these days. But free nights won't always save you money. That's because the "free night" may be calculated at a nightly rate that's higher than other rates available at the same property. When assessing whether a deal will save you money, always follow our recession travel rules. Number 28 is to compare apples to apples.

Wyndham's "5th Night Free Plus $100" deal seems straightforward at first ( When you stay at least five nights at any in a long list of Wyndham properties in Mexico and the Caribbean, you'll get your fifth night free plus an American Express gift card worth $100. You might think that getting one night free during a five-night stay would mean a 20% reduction of your bill. Seems like a no-brainer, right? Not so fast.

At the Wyndham Sugar Bay in St. Thomas, for instance, the "5th Night Free Plus $100" package rate starts at $219 a night, compared to the lowest available rate of $170 a night, which is an advanced-purchase nonrefundable rate. Even after you subtract the cost of the free night, you'd pay $876 for a five-night stay, versus the $850 you'd pay for five nights at the advanced purchase rate. (True, when you factor in the $100 gift card, the package nets out as a $74 savings. But you wouldn't be able to use the $100 gift card on your trip. You'll receive your gift card in the mail six to eight weeks after you get back home. )

A better bet at the same property is the Caribbean Vacation Stimulus Package, which gives you two free nights when you buy two nights, plus a $100 food-and-beverage credit. As with the 5th Night Free package, the rate for this package starts at $219 a night if you travel between August 25 and October 31. (It jumps to $294 a night in November.) With this deal, a four-night stay in September or October will cost $438, an average of about $110 a night, which beats the lowest available rate by $60 a night. Plus, you'll get $25 a day shaved off your dining costs. Jackpot!

The Caribbean Vacation Stimulus Package is good through November 30 and can be booked online with promo code PKGCARIB1. The 5th Night Free deal is good through December 30. To reserve either deal by phone, call tel. 800/WYNDHAM.

Meanwhile, our recession travel rule no. 11 is a mandate to visit the web site of your chosen destination's tourist board before you book a vacation. Not only is the typical tourist board a fountain of useful practical information, but it will likely have the inside track on travel discounts, too.

That's especially true this year on Kauai, which has made a name for itself as a Hawaiian haven for active, eco-friendly, outdoorsy types. The Fall Specials from the Kauai Vistors Bureau ( prove that prices can be equally down-to-earth. A great example is the Castle Kaha Lani Resort (, where a one-bedroom, ocean-view condo can be nabbed for just $149 a night (down from $235 -- a savings of nearly 40%!) through December 18. The condos have full kitchens and private lanais, and the resort has a pool, tennis courts, barbecues, a putting green, and a coastal walking path great for some impromptu family hikes. You're also next door to the very family-friendly Lydgate Park, a well-equipped county beach park with lifeguards and two cordoned-off areas for snorkelers and beginner swimmers.

More good news: The Fall Specials extend to cool activities, too. For instance, we loved the prospect of the 15%-off deal (worth about $45 in savings for a family of four) for the five-hour hike- and-paddle tour of "Secret Waterfalls" from Kauai Kayaks ( is an authoritative online guide to family trip-planning. The site features reviews of kid-friendly hotels and resorts, expert planning advice, readers' travel tips, destination insider guides, regional getaway ideas, vacation deals, and more. Subscribe to our newsletter to hear about resort specials and exclusive, money-saving offers. Follow us on Twitter at @WeJustGotBack.

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