These have since been paid, but Ward said the nature of the breaches meant almost all employees were affected.
2 Cheap Cars was ordered last November to audit its records, which has so far uncovered estimated arrears of more than $250,000.
A second external audit is now being done, to ensure all current and former workers have received their correct entitlements.
"Not only did the employer breach the rights of the people working for them, they also attempted to gain an unfair advantage over their law-abiding competitors," Ward said.
"A number of the employees were migrant workers who may not have been aware of all their rights and entitlements.
"Every worker in New Zealand must be paid at least the minimum wage for every hour worked, along with their holiday and leave entitlements."