Aren't there little commission free booths in the city? Little box like things or small shopfront, worth walking around to different ones to find the cheapest, they have them in some other cities, not sure of Brisbane though. The rates are normally much better than the banks, no catches either, I've always wondered who owned them- maybe at the bottom of some money laundering scheme? Look like franchises. btw, the booths would normally be near high traffic tourist areas like cinemas or street malls.