seen https://pricemycar.com.au/
Seems to do for new cars what redbook does for used cars could be useful - choose model and it gives you what people have paid recently eg
Lexus IS350 LUX
Excellent Price
Driveaway: $68,902
Saving: $2,524 or 3.53%
starting point for haggling
EDIT: Actually redbook does for new cars too seems to check out https://www.redbook.com.au/cars/details/2019-lexus-is350-luxury-auto/SPOT-ITM-519079/