A new website has been launched aiming to weed out cowboy car dealers through consumers rating dealerships.
Buyerscore reviews are triggered by point of sale receipts, with a customer then being sent an online survey.
Mark Greenfield of Buyerscore told 1 NEWS dealers "have either learnt and confirmed how good they were and the service they were giving, or they have learnt areas where they were falling down".
Just over 230 dealerships are using the online tool, he said.
The platform is also set to work in conjunction with the auto pages of Trade Me.
Last year, there were more than 400 complaints to the Commerce Commission about vehicle sales.
That's a 17 per cent increase on the year before, and most of those complaints relate to second hand car dealers.
"For some of these dealers, it will be deliberate and willful conduct that's intended to be deceiving. But for others they won't be aware of their obligations under the Consumer Guarantees Act," Ritchie Hutton of the Commerce Commission said.
Problematically, some are passing themselves off as private sellers to avoid trading obligations.
The commission is promising more investigations as part of an enforcement crackdown.