Hi Dave,
There are two ways to change ownership..
1. Transfer the rego and ownership with a valid RWC. The RWC has to be done by a licensed tester. Sometimes the seller pays for the RWC or the buyer might agree to pay for it.
2. You hand in the plates (and maybe get a refund on part of the reg) and sell it unregistered. The new owner has to then get the car re-registered which requires an inspection. Not sure if Vic Roads has to see the car or if they'll accept a RWC.
cheers,
JohnH