Just came across the BOGO sale (Buy one and get one free) at ELF cosmetics. If you scroll into the sale section you will find cosmetics as low as $1 and when you add it to your cart it is $0.00. You only need to pay $9 for AUSPOST Standard shipping. You can also see other makeup items where you get 2-for 1. Now that's quite a deal!
Beware of the way this website calculates BOGOF. It will keep taking the cheapest item as the free item. So for example, if you had this in your cart:
2 identical items $35 each
2 identical items $6 each
The total will come to $70, instead of $41 as you would expect, even if the items are identical. It is not a true BOGOF