Every Australian state and territory taxes a property purchase with a "transfer duty" — old-school name: stamp duty. The rate scales with the price, but each state has its own schedule, threshold, and set of concessions for first-home buyers.
On the same $850,000 purchase, the duty bill swings from around $0 in the Northern Territory to roughly $45,000 in Victoria. That's a 5% swing in the upfront cost of buying, just from which capital city you're in.
Two big levers can shrink it: the first home buyer exemption (most states wipe duty entirely up to a threshold), and the off-the-plan concessionin NSW & VIC (you pay duty only on the land value at contract date, not the completed dwelling).