At the blue slip joint the owner would've gotten an unregistered vehicle application form.

Assuming that it had passed, you agree on price and have a receipt written out to you (including vin/chasis number, engine number, colour of car, kms reading on the odometer, purchase price, seller and buyers details date of sale) you then go an get a 12month green slip (no number plate recorded)

Take your license, blue slip, green slip, receipt of purchase and the cars old number plates if it got to the rta and bingO!

You wont need to pay for any transfer fees but you will need to pay for a 12 months green slip, new number plates, 12 months of rego and the stamp duty on the price of purchase.

True story, it happened to me last week the end.