Roadworthy Certificate information for Melbourne and greater Cheltenham residents. Need a Roadworthy Certificate? Book online with your local RWC Authorised Service mechanic today. The Cost of a Roadworthy Certificate depends on the Licensed Vehicle Tester aka the Mechanic that is Licensed by VIC Roads. The Cost of a Roadworthy Certificate? The cost of obtaining a Certificate of Roadworthiness is not fixed. It may depend on the age, type and condition of the vehicle being examined.