CHICAGO (CBS) — As cars get more sophisticated, it is getting easier and cheaper for thieves to break in and drive away with them – especially when it comes to keyless cars.

Cars that can start without the driver taking keys of a pocket are easy targets. In the latest trend, even if you are parked along the street and run into the store, thieves can trick your car into thinking the key is right next to it.

Brinton Flowers was in University Village when the keyless 2018 Benz was stolen.

“It’s a pretty easy job, stealing that vehicle. No muss, no fuss, no hotwire,” explained Perry Myers, a private investigator and owner of U-Spy.

Myers demonstrated how it works at his client’s home in Bolingbrook. The key was inside the house.

“Once he picks up a single, he takes that signal and he transmits that signal to the second guy who is able to open up the target vehicle and then start it,” he explained.

Thieves are using a device that can be found on eBay for under $80.

“It’s funny because eBay doesn’t allow lock picks to be sold on their website, but these things they can sell,” said Myers.

Myers recommends putting car keys in a blocking wallet made of metal. The wallet blocks the key from being tapped into by not allowing radio frequencies through, ultimately protecting you and your car.

Relay signals can also go through walls, doors, and windows.

“Keep that key somewhere in the center of your house,” Myers recommends.