Yes it is worth buying from Govt auctions. I saved around four grand on what a dealer wanted at the time, and that was paying reserve for a passed in car. As for an ex cop, well just be aware that they will have been worked hard and that will be right from word go, when the running in period should have occurred, they will have been driven just as hard as a car with ten grand on the clock. By finding out who had the car in the first place, you can maybe opt for an ex education or health system vehicle (probably won't have been thrashed) This, however may rule out the possibility of obtaining an SS as not sure if other departments use these. Bit of ringing around will help, though. In QLD it's all handled by the Public trustee.