I notice you're from Perth.
If it helps, I have just bought a Z3100 44inch through Artref in Perth for just over AU$14000. At the time they quoted me under AU$9000 for the 24inch with the stand.
Besides the price, the other issue I have with HP in Australia is the availability of the HP papers. HP Pro Satin is not yet available though I have been promised that it is on its way. HP Hahnemuhle Smooth Fine Art, a paper I particularly wanted to try, is a special order from Europe!
The printer is good though