Summer may be the time to take it easy, but don't let your guard down against con artists with offers that are too good to be true.

There are plenty of warm-weather scams to be aware of, whether you're planning a summer vacation or working on home repairs, says Katherine Hutt, a spokeswoman for the Better Business Bureau.

Here are five summer scams to watch for and advice on how to avoid them.

The 'Great' Vacation Rental

The Federal Trade Commission issued a warning about vacation rental scams this month. Here's how they work: You see an ad on the web for an attractive vacation rental at an even more attractive price. To book it, the ad says you must wire an advance payment, and it provides instructions. 

More on Scams

After you do that, one of two things typically happens. Either the contract for the rental never arrives or you receive it, sign it, and head to the house only to find that it doesn't exist or that it's locked up and there's no one to let you in. In the worst case, you’ve lost the advance you paid and you have no accommodations.

Don’t fall for it. One way to stay safe is to avoid vacation rentals posted on free online classified ad sites such as Craigslist, says Hutt. Instead, she recommends using a dedicated third-party rental site that provides protection. Two examples are Airbnb and HomeAway.

The BBB also recommends visiting the house or apartment before paying for it. If you can't and know someone who lives near the location, ask him or her to check it out for you.

A Home Improvement 'Special'

A contractor stops by your house unexpectedly and says he just happens to be repaving a driveway nearby and has leftover material. He offers to repave your driveway for a really low price.

Or a contractor looks at your chimney or roof and tells you it needs to be fixed even if it doesn’t. In such cases, he either takes your money without completing the work or he does a shoddy job.

Summer brings a spike in the number of unscrupulous contractors going door to door trying to sell such services, says the Minnesota attorney general.

Scam contractors often emerge after hurricanes, wildfires, and other disasters strike, warns the Insurance Information Institute. “Unfortunately, there are dishonest service providers that prey on disaster victims," it says. "They know that people who have lost their homes and valuables may not be thinking clearly."

Home improvement scams reported to the BBB last year left consumers with a median loss of $1,255, says Hutt.

Don't fall for it. Beware of anyone offering to do a repair unsolicited, Hutt advises. When looking for a contractor, get referrals from family, friends, and others. And before agreeing to work with one, verify that the contractor has complied with the licensing and registration required by your state.

A Low-Cost Move

You search the web for a moving company that can transport your belongings without charging hefty fees. You choose one, and after the move is underway, the mover doesn't deliver your items to your new home.

Instead, he holds them hostage until you pay more. Such scams are not unusual. There are many unlicensed, rogue movers out to take advantage of the summer moving season, according to the American Moving & Storage Association

Don’t fall for it.
 If you’re moving out of state, verify that the moving company has a valid Department of Transportation number and a carrier number from the Federal Motor Carrier Safety Administration. For in-state moves, check your state's licensing requirements.

Also, before choosing a mover, ask people you know for a recommendation.

Hiring a local mover with a good reputation can help you avoid being scammed, says Scott Michael, the moving association's president and CEO.

Discounts on Hotel Stays

When searching on the web, you find what appears to be the website for a hotel in which you'd like to stay. It has a photo of the hotel and the rooms, the address, and the phone number, and it also lists the amenities and prices. The web address even includes the name of the hotel, which makes it look legitimate.

But the site is actually run by a third party that wants you to believe you're dealing directly with the hotel, says Maryam Cope, vice president of government affairs for the American Hotel and Lodging Association.

After you input your credit card information, you may find that a reservation was never made and that the scammer now has your credit card details.

In other cases, the site will make a reservation for you but charge you more than the hotel's regular rates. It may also charge extra fees to your credit card, Cope warns.

Don’t fall for it. When searching for a hotel online, read the "about" page, which may give you an indication that the site is operated by a third party, Cope says. Also look for other evidence that the site might be run by a different company, such as a third-party logo.

If you book through a third party, Cope recommends verifying your reservation directly with the hotel.

A Free Home Alarm System

A salesperson shows up at your door warning about a recent rash of burglaries in your neighborhood. But it's your lucky day because you're eligible for a home security system, totally free.

The salesman, however, requires that you sign a multiyear contract for the company's monitoring services. He may also falsely claim that you must act immediately to take advantage of a limited-time offer, the Federal Trade Commission says.

In a related scam, a person claims to be a representative of your current alarm company, which is upgrading customer equipment. But instead of installing an upgrade, Hutt says, the person puts in equipment from another company and tricks you into signing a second monitoring agreement.

Don’t fall for it. Never buy a security system from someone who shows up at your home or calls you with an offer that sounds too good to be true. Find out how to select a security alarm system by doing research on a site such as the one run by the Electronic Security Association, the FTC advises. If someone shows up claiming to be from your current provider, verify with the company before signing anything or agreeing to changes in your system, says Hutt.

Scam-Proof Yourself

The best way to avoid scams like these is to make sure you check out the company or the individuals you plan to work with before agreeing to do business, Hutt says. You can do this by searching on the web for the company, including such words as "review," "complaints," and "scam."

It's also a good idea to look for a report on the BBB's website for any company you are considering working with, she says. That could alert you to one that may try to scam you.

Another suggestion: Whenever possible, pay with a credit card. That way, you can dispute any charges if you're scammed, she says.