luckydog, there certainly is the availability to return your Hertz car at BNE International (as there are dedicated rental car lanes as you enter the airport area), although I will hasten to add that I cannot recall any Hertz Desk inside the International Terminal. I can only presume that the return area (perhaps better known as a "shed") is located in the carpark (similar to the returns area at BNE Domestic). I can't say that I have ever looked for it (being a local, I've never returned a car there)....
Successfully picked up car at Brisbane domestic and returned it to Brisbane international. There was one of those returns people with the handheld computer and it was all done very quickly with zero fuss and with a very short walk to the terminal.
Plus paid for the cheap camry and got a very nice Nissan Maxima so that was a double bonus.
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