A couple, hoping to sell a gaming system, came face to face with three would-be robbers and now the Sheriff's Department is warning others who use popular apps to buy and trade.

The two victims say they were "set up" by their attackers who arranged a meeting on the popular app "Letgo". 

It was on the popular buy and sell app "Letgo" where a Hixson woman says she first met Charley Daniel.

They say Daniel had agreed to buy two PlayStation gaming systems for $200 dollars. The victim went with a male friend to meet Daniel at an address in the 7900 block of Boston Lane. It all checked out until the victim says Daniel asked them to step into a neighboring home to make sure the equipment worked.

According to a police report, that's when Joseph Hood and Lee Ann Brock showed up with a knife. The victim told authorities that all three suspects "ganged up" on them in an assault. 

So many people make a living scamming other people and if you threaten their ability to do that a lot of them will not hesitate to hurt you.

Chief Deputy Allen Branum says it's never safe to meet a stranger online for a sale especially in an unknown place. This case is a perfect example. 

"Avoid anytime you can, having people in your house or going to anybody else's house," said Chief Branum. "That might not even be their house." 

The couple got away with their valuables and called 911, but the suspects chased them down in their car and blocked them in near a moving train. Once the train passed they drove off.

"They say well it's only a $100 dollar purchase, but $100 dollars there are people that kill for less money than that," said Chief Branum. 

Officials say if you are going to make any deal, you should always choose a busy public place and preferably one with lights and surveillance cameras. 

In a bizarre twist, police say the trio had an 8-year-old child with them during the attempted robbery. The victims say the child tried to stop the assault. Authorities are now looking into the welfare of the child as all three suspects face robbery, assault and conspiracy charges.

When using apps to buy, sell and trade, Authorities suggest finding a designated safe zone or well populated area.

To find a local zone in your area : CLICK HERE