AFG's strongest July in five years is being attributed to a "powerful cocktail of incentives" luring first-home buyers into the market.
The brokerage processed the highest amount of mortgages last month since July 2007, amounting to $2.7bn.
The percentage of first-home buyers also spiked, to 17.3%.
"Low interest rates, soft property prices and escalating rents create a powerful cocktail of incentives to get people into the property market," said AFG's general manager of sales and operations, Mark Hewitt
For those refinancing, non-majors jumped in popularity to 26.7% of the market share.
Meanwhile, the number of fixed-rate loans continued to plateau, as variables proved more popular.