Dodge the airport fees. Picking up your car in Toowoomba's city centre is often cheaper than grabbing it at the airport, as you avoid the premium location surcharge.
Time your booking. If you're coming for the huge Carnival of Flowers (September) or over the summer holidays, book your car well in advance. For quieter times, you can often find a bargain by comparing dates.
Fill 'er up before you go back. There is no petrol station at Toowoomba Wellcamp Airport (WTB). Top up the tank in town before you return the car to avoid expensive refuelling fees.
Play with your rental dates. Sometimes booking for a full 5 or 7 days can be cheaper per day than a shorter 3 or 4-day rental. It's always worth checking.