Humble currently has The Witcher 3: Wild Hunt on PC for cheap.
You can grab the game off the store for $11.99 AUD for the next four days. You can get it HERE. This is a saving of 70% off the RRP.
If you’re after the expansion pass (which includes both DLC expansions), that’ll set you back a further $9.99 AUD and you can grab that HERE. Alternatively, if you’re after just Blood and Wine or Hearts of Stone, they’ll set you back $7.99 and $3.99 respectively.