This one will be super quick!
I recently discovered an auction site called Top Hatter which auctions off items from bed linens, to designer watches and purses and even makeup. I recently purchased a Tarte skinny smoldereyes in Azurite Green for 1$. This site ships to Canada and US, as far as I know but US has much better shipping than Canada. I paid 7$ shipping which is nuts, but paying only 8$ total is still cheaper than buying that eyeliner elsewhere. Some things go for equal or more than their worth, but a lot of things are steals, you just need to know your prices.
Here is the link to the site, I recommend checking it out. They sometimes have special auctions with just Smashbox, Tarte, Benefit, Urban Decay, etc. https://tophatter.com/sign_up?campaign=link-invitation&invitation_id=238d69&source=invite