Rough average seems to be around 350 Dual, 270 Solo
Those figures are about right if you are flying at a busier airport like Bankstown when you include landing costs. If i was you and live in NSW i would be looking at the less busy airports like Moruya and Camden, they also have some very old and very experienced instructors who have been instructors for decades. I know at Moruya it is definitely cheaper too (especially dual hours).