Does a commission payable to a real estate agent in Queensland, Australia include a GST component?

Does a commission payable to a real estate agent in Queensland, Australia include a GST component?

For example, if I sell my house for $500,000 and the Agency listing it for sale charges a commission of "3.3% of the sale price including GST", does that mean that the commission payable on the $500,000 is simply $17,500 (3.3%), and the GST payable to the ATO must be taken out of the $17,500? Or is an extra 10% of $17,500 added to the commission fee...........

Bit confused