CHICAGO (WLS) -- The I-Team is exposing an illegal practice known as "curbstoning" which can leave consumers with no recourse.
You could be a victim and not even know it. Curbstoners are people who may look like real car dealers, only they don't have the proper license. That means they could sell you a clunker and then disappear.
They're easy to find: Clusters of vehicles with "for sale" signs at gas stations, restaurants, fenced-off parking lots and on the curb.
"It's illegal to have a for sale sign in your vehicle in the city of Chicago whether it's on a street or whether you're talking about curbstoning on a private property," says Maria Guerra Lapacek, Business Affairs Consumer Protection.
"Curbstoning" is a term which comes from the age old act of selling items by the stone of the curb by car dealers who don't go through the licensing process and have no established place of business.
"They basically fly under the radar," says George Mitrofski, a used car dealer.
Legitimate used car dealers like Mitrofski and Anthony Kessel say curbstoning cuts into their sales.
"My business probably is down close to 50 percent," Kessel says.
"You may actually be buying yourself a problem because they turn back the odometer in these vehicles, they're actually salvaged and they hide any kind of mention of that. There are people who doctor titles," says Lapacek of the dangers to consumers.
The I-Team found two curbstoned vehicles you'd want to avoid. According to CarFax and Auto Check Reports, they both potentially have rolled back odometers. One was being advertised as having 96,000 miles but according to the reports has 145,000.
"If you have a problem, you'll never find them," says Mitrofski.
But you can figure out who they may be, before you buy. We copied phone numbers from private seller ads on Craigslist and then pasted them in the search engine. Dozens of vehicle ads were connected to each individual phone number.
We responded to one ad. The car was located at a gas station on the city's southwest side. In the state of Illinois the law says unlicensed, private sellers can't sell more than four cars a year. This one ad was connected to eight cars for sale.
The city says the commercial use of space for selling a vehicle is not allowed unless you're a licensed dealer.
After confronting employees at the gas station connected to the car for sale ad, four cars - all for sale with phone numbers on them - were quickly moved off the property.
If you're buying a vehicle from a private seller, the Better Business Bureau says you should have it checked out by an independent mechanic, make sure the name on the title matches their license and run the VIN history on sites like Auto Check and CarFax.
"Why would a guy on the street want to sell you a car for $2,000 less than what it's worth," Kessel asks.
In the last two years the secretary of state's office has arrested about THREE dozen people and even recovered four stolen vehicles.
In 2012, Alderman Ed Burke asked for a city wide crackdown and that action resulted in almost 100 citations.
It's estimated that millions of dollars in sales tax revenue are lost due to curbstoning.
Watch ABC7 News at 5 p.m. on Tuesday, May 10, to see a recent curbstoning sting which was executed by the city's consumer investigators.
Rogue car sellers use 'curbstoning' to cheat customers