Vehicle retailer 2 Cheap Cars is facing charges over ad claims and making customers sign 'warranty waivers'.
A Commerce Commission investigation was launched in November 2017 after it received several complaints.
It's after the retailer advertised a 'liquidation sale', when most vehicles were not discounted at all, or were $5 cheaper than normal.
It's also estimated more than 20,000 'warranty waivers' were signed between January 2014 and December 2017.
The waivers state, among other things, that customers are solely responsible for any repair bills.
However, under the Consumer Guarantees Act 1993 consumers have rights of remedy against suppliers regardless of whether the goods are covered by any other warranty.
2 Cheap Cars is facing 10 charges and the matter is now before the Court.