A fifteen-year-old boy died in a high-speed crash just before Christmas in a car bought online for €400, an inquest heard.
Front-seat passenger Dayne Cody was pronounced dead at the scene.
The transition-year student was one of five young males travelling in the 2.5l Kia Magentis that spun out of control and hit a tree on Station Road, Clondalkin, on December 20 2014.
Dublin Coroner's Court heard the car was advertised for €500 and the registered owner had given a real name but a false address and engaged a seller who was paid €50 to sell it.
"The owner got €350," Det Insp Richard McDonnell told Dublin Coroner's Court, adding that the unregulated sale of cars on websites such as Done Deal is a "major, major issue".
"We have had incidents where two or three cars have been made into one, it happens on a regular basis," Det Insp McDonnell said.
Coroner Dr Brian Farrell said it was an area "in great need of regulation".
"It just seems anyone can purchase anything from this website and there is no regulation," he said.
Giving evidence, the driver told the inquest he was 16 when he saw the car for sale online and took the bus to Swords to buy it.
He got off the 41 bus at the last stop and paid the seller €400 for the car. Later, with friends, he was driving to get petrol when he saw a Garda van and sped up at Station Road.
"I thought they were coming after us," he said in his deposition. "I woke up screaming for help."
The driver, who had no licence, was convicted of dangerous driving causing death on November 19, 2015. He was sentenced to 16 months' detention.
Gda David O'Brien said: "There are no rules or regulations . . . as regards selling cars that are not roadworthy, anybody can do it. The person selling it doesn't really care about who they are selling it to."
The rear tyres on the car were well worn, one excessively, forensic collision investigator Garda Edward Davin said.
Dayne Cody - from Barnville Park, Ballyfermot, Dublin 10 - was pronounced dead at the scene.
He died of multiple injuries consistence with a road traffic accident. Toxicology reports showed neither he nor the driver had taken drugs or alcohol.
The jury returned a verdict of dangerous driving causing death in accordance with the Circuit Criminal Court finding.
The coroner said he would contact the Department of Transport to convey the jury's recommendations, which include measures to prevent the selling of cars without a valid NCT and to underage drivers.