They’re the modern day equivalent of old-fashioned garage sales.

Have things you’d like to get rid of it? Post it online. Looking to buy something you can’t find in stores? Search online. Websites like Craigslist have created a virtual market for buying, selling or trading just about anything.

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Despite the popularity of the sites, transactions aren’t always safe. Three recent deaths in metro Atlanta, plus a fourth man’s mysterious disappearance, are the latest reminders that both buyers and sellers need to be on high alert to avoid becoming victims.

The Florida-based Advanced Interactive Media Group has tracked 112 deaths related to Craigslist, including several in Georgia, said Peter M. Zollman, a consultant with the group. But it’s not fair to fault the website, he said. And Craigslist isn’t the only site used to sell everything from cars, iPhones and sneakers.

There is a multi-agency manhunt going on for the people who killed two men during a robbery in Walton County.

“The fault lies with the people who actually commit the crimes,” Zollman said. “Craigslist could and should do much, much more to promote and encourage safe use and the safe-trade stations.”

According to Craigslist, the rate of violent crimes is extremely low compared to billions of safe transactions.

"The overwhelming majority of Craigslist users are trustworthy and well-meaning," the company states on his website. Among its tips for users, Craigslist encourages meeting in public and bringing a friend when meeting a stranger. Instead of a parking lot, insist on meeting at a police station, according to law enforcement.

“We’ve got the technology here; it’s on camera,” Officer Louis Defense with Smyrna police said. “You’re just safer here at the police station.”

If a potential buyer or seller isn’t willing to meet at a police station, that should be a red flag, experts warn. Picking a public place isn’t always safe — even during daylight hours. And be wary of deals that seem too good to be true, police said.

On May 1, Vicente Cruz, 44, of Austell, drove to northwest Atlanta to show a potential buyer his 1989 Ford F-150 pickup he’d posted for sale on Craigslist, according to police. Cruz had a friend go with him, but told her there was no reason for her to stay. Cruz wanted to give the buyer time to look over the truck, he said. He hasn’t been seen since.

Cruz's truck was later found abandoned in a motel parking lot and there was blood inside, according to Atlanta police. Foul play is suspected, and anyone with information on the case is asked to contact police.

Days later, Mezaio Pickett, 26, exchanged messages with a man selling shoes on a website called OfferUp, and on May 8, he agreed to meet in the parking lot of a Carrabba’s restaurant on Cumberland Parkway, according to police. Pickett paid for the shoes and after he had them, the seller came with a gun to try to get the shoes back, his girlfriend, Porchia Rivers, told Channel 2 Action News.

“From my understanding, I was told he was trying to back away and telling them, ‘Don’t worry, you can take whatever,’” River said. “(He) pleaded for his life and you still shot him.”

Two days later, Vincent Brooks and Damien Scott, both 22, were arrested and charged with murder. Pickett is survived by five children.

On Monday, two men made the 75-mile drive from Meriwether County to Walton County to sell an item after posting it online, according to police. Instead, the men were lured to Clegg Farm Road to be robbed and both were shot multiple times, Walton Sheriff Joe Chapman said.

“Robbery, it was a transaction, some social media-type transaction, Craigslist-type situation,” Chapman said.

The two men, whose names have not been released, were found dead inside a truck after it crashed. But investigators quickly determined the men weren't killed in the crash. A 16-year-old has been charged with murder, and investigators continue to search for other suspects.

In a high-profile case that shocked a Cobb County community, an older couple was killed in January 2015 allegedly by a man that claimed to be selling a vintage Ford Mustang. Bud and June Runion drove 200 miles from their Marietta home to McRae, but there was no car. Both were shot in the head and found in a wooded area days later.

It’s the anonymity in using sites like Craigslist that can lead to problems, Zollman said. That’s why neighborhood “garage sale” groups on Facebook may be a safer option to sell or buy, he said. On Facebook, it should be easier to detect if someone is not who they say they are and avoid potential scams.

Despite the news reports of online sales ending in tragedy, many that use the websites don’t believe it will happen to them, experts say. Zollman said continuing to educate the public is important.

“It’s a total tragedy that people continue to be killed through innocent use of such a wonderful resource,” he said.