The rule in all states is that the vehicle is required to be registered in the state in which it is normally domiciled. Registration and driver's licences are required to be changed within a certain period of taking up residence in that state. Qld used to require change after two weeks, but this may have changed. I once had a sales rep based in northern NSW with his company car registered in Qld at the corporate address. He received a fine for having an interstate registered car kept in NSW and was warned to get it registered in NSW within xx days or he could be fined every time the local coppers saw him. I contacted the then Dept. of Transport in Grafton and this was confirmed. We had to register his car in NSW, considerably more expensive than Qld, at his address and with the Qld. postal address recorded for service of notices. At one time Victoria would accept interstate registration addresses but this was just a petty registration monies grab to get funds from big fleets operating interstate with head office in Victoria.

