It’s hard to imagine a worse ending to a summer vacation than returning to find that someone broke into your home. And while it's true that there's not much you can do to thwart the professional burglar, according to University of Pennsylvania criminology professor Richard Berk, that's not who you need to worry about. "Most burglaries are done impulsively, by kids," Berk says.

The good news is that you can do a lot to stop home invasions by making some simple household fixes and upgrades. Indeed, the Federal Bureau of Investigation estimates that nearly 90 percent of burglaries can be prevented.

Now's the time to do something about it.

Summer, when many people take a week or two off for vacation, is peak season for burglaries, according to the U.S. Department of Justice. Here are five ways to make would-be thieves think twice before breaking into your home.

1. Start With a Great Lock

At Consumer Reports, our test engineers find big differences when they evaluate deadbolt door locks for their ability to resist being kicked in, drilled, or picked. And price is no predictor of quality.

The highly rated Kwikset 980, for instance, is a bargain at $30, having earned perfect marks in CR's kick-in and picking tests. On the other hand, the pricey Yale Real Living Touchscreen Deadbolt YRD220-ZW-619, $275, received the lowest score possible in our kick-in test when installed with its factory screws.

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What's the difference between the two? The Kwikset comes with a heavy-duty strike plate and 3-inch screws to anchor it securely, while the Yale has a standard-gauge strike plate and 3/4-inch screws.

“Using screws that are too short means the strike plate is attached only to the door jamb, and those are often made of soft pine," says CR test engineer Dave Trezza, who runs the lock program.

At least that's a weakness you can easily fix. “With just about any deadbolt, you can seriously beef up its out-of-the-box performance by installing a 4-screw box strike plate with 2-inch screws that go beyond the jamb to catch house framing,” Trezza says.

2. Lock Your Windows

No less than 30 percent of burglars gain access to a home through an unlocked window or door, according to a report published by the Department of Criminal Justice and Criminology at the University of North Carolina at Charlotte. So lock your windows and doors, folks. 

3. Put On a Good Show

Taking steps to make your home appear occupied when you're away is an effective way to deter burglars, according to Berk. “Leave items in your yard that make it look like you’ve got a dog,” he adds, and “put a few lights on an automatic timer, so it looks like people are home.”

Products such as the BeOn Home Protection System, $129 for three LED bulbs, automate that process. The included LED bulbs learn your lighting habits and replicate them when you’re away, making it harder for burglars to notice an abrupt change in your household routine.

It's also a good idea to install pathway lighting and keep bushes trimmed, particularly near windows and doors. And ask a trusted neighbor to pick up any packages that are left at the front door while you're away. But don't tell the world your plans—the Bureau of Justice Statistics reports that more often than not, burglaries are committed people you know. 

4. Look for Weak Spots

A thoroughly secured front door won’t do much good if you leave other entry points, like a cellar door, unsecured. Those are best locked from inside, rather than with a padlock on the outside, which can be cut with bolt cutters.

Garage doors are another weak point: Some older models can be opened with a wire hanger, and even modern models can be hacked. A device called RollJam, first shown at an annual hacker convention called DefCon in 2015, costs a mere $32 and can crack codes on many automatic garage door openers. So pay extra attention to the door and lock that separate your garage from the rest of your home. Better yet, unplug your automatic garage door opener, rendering it inoperable while you're away.

Window air conditioners introduce an inherent security vulnerability because they make it impossible to secure windows with their sash locks. Consider using a dowel, or preferably a locking metal rod called a Charlie bar, between the top rail of the open sash and window jamb. That way, a would-be burglar can’t simply slide the window open—they’ll be forced to break the glass, attracting attention in the process.

5. Consider a Security System

“Get a home security system and display the sign prominently,” advises Berk, the University of Pennsylvania criminology professor. According to the FBI, on average, only 12.4 percent of burglaries end in a conviction. In other words, the majority of burglars get away with their crimes, a fact that probably emboldens a fair share.

Buying a home security system, or at least adding a few signs to give that impression, says Berk, makes your home less appealing than others in the neighborhood to any thief who's paying attention.

It's just one of a few simple steps you can take to protect your home. “It’s not rocket science,” Berk says, but these steps can dramatically reduce the chances of a break-in while you're away.