The 50-plus crowd has a serious collective case of wanderlust. The average 50-something makes five trips every year, according to AARP's Travel Trends survey, accounting for nearly half of all vacation spending among U.S. consumers, and 80 percent of the nation's luxury travel budget. That's about $120 billion a year!

If you fit into this demographic, and are thinking of taking a trip soon, it can be tempting to build a travel fund and then blow it all on a big, ambitious getaway. But if you follow some well-tested cheats, you might be able to stretch your budget, and spend even more time on the road than you hoped. Here are four ways to travel more for less:

1. Get the most out of hotel loyalty programs

Major hotel chains like Marriott and Hilton will sometimes knock 5 to 15 percent off your room rates with special offers, TravelClick senior industry analyst John Hach tells the Los Angeles Times. Many also throw in free Wi-Fi (sometimes a hidden add-on), room upgrades, and similar perks.

The program will send you special offers periodically, too. "If you don't want your inbox cluttered with promotional emails that come with membership, create an email address for those loyalty programs," suggests Catherine Hamm in the Los Angeles Times. Just be sure to check it from time to time. Also, you can speed up the points you accumulate with each stay by getting a hotel-branded Visa or MasterCard, earning points for what you spend. It can add up to free nights fast. If you've got other ways to line up accomodations, maybe an airline credit card would help. If you use your cards a lot, you might be surprised how quickly you can line up a free trip.

2. Exchange homes with compatible travelers

Finding hotel deals isn't the only way to cut travel accomodation costs. Trading houses is a good option, especially if you happen to live in a place people like to visit.

"House swapping or home exchanges have been around for a while," says Keith Hockton at International Living. "Nowadays there are several websites offering the service, where you meet like-minded people and agree to swap your home for theirs, sometimes even your car."

Signing up for these services is a pretty simple process. It costs around $15 to $20 a month to offer up your place at sites like HomeExchange.com or LoveHomeSwap.com, but you save way more than that if you use the service to travel once a year, or even less frequently than that.

You'll have a chance to get to know the people you're swapping with ahead of time, to ease any fears you might have about handing over your keys to a stranger. "I wondered if it was safe," says Hockton. "Now, after several swaps of my own, I know it is. The exchange company we've used happily has been in business for 19 years. After tens of thousands of exchanges, it has never had a report of theft, vandalism, or of someone getting to their exchange home and finding a vacant lot."

3. Try housesitting

Of course, there are other ways to find a house in a faraway place. You can rent a cottage or a house, of course, for a cozier and more independent alternative to hotel living. You can also try something that might be harder to arrange, but with a bigger potential payoff, like housesitting. "If you're setting off on your part-time adventure and you're on a limited budget, housesitting can be a great way to offset your accommodation costs," says the staff at International Living.

Finding a housesitting gig overseas might have been a difficult thing to swing a decade or two ago, but these days the internet offers a variety of sites that can help. Sign up at Trusted House Sitters, House Carers, Mind My House, or a similar websites and you'll be able to check out your options and contact owners.

"Housesitting is the key to our lifestyle," says veteran housesitter Yvonne Bauche. "Over the last few years we have housesat in a 15th-century home in London, a Tuscan farmhouse, a French vineyard, a Spanish casita, a luxury villa in Costa Rica, deep in the Belizean jungle, and in several ocean-view villas in the Caribbean. We estimate we have saved over $150,000 in accommodation costs by housesitting and have gained unique insights into different retirement lifestyles."

4. Plan ahead, and be flexible

If you can map out your plans in advance — and commit — you're a step closer to getting more out of your adventure, and paying less for it. "Hotels offer discounts for pay-in-advance guests who are betting on being able to make the trip and thus lock in their rate," says Hamm. "The downside: If you must cancel, you may not get your money back or, if you do, you may pay a sizable cancellation penalty." There also are many ways to save on airfare. Use a travel site (Kayak, Travelocity, CheapoAir.com, to name a few) or more specific service such as AirfareWatchdog.com to alert you when fares to your desired destination drop. And be flexible — you can sharply reduce your fare sometimes if you can tweak your departure or arrival date, or switch to a nearby airport.

One other factor is timing. Many destinations are far cheaper off-season. Whenever you plan to actually go, you should avoid booking too close to travel time, or too far in advance. According to a study by CheapAir.com, the ideal time to book your travel is about 50 days before your departure date.