Hey look, another Mini.

http://backpack.tf/item/5317715697

Sale 1) Sold for 9 Keys + ~1 Key of Items

http://backpack.tf/profiles/76561198084792603#!/compare/1493856000/1493942400

9 + 1 = 10 Keys

http://backpack.tf/item/1074492125

Sale 2) Sold for a Smoking Sultan's Ceremonial (10.5 Keys) + ~0.7 Keys of Items

http://backpack.tf/profiles/76561198061826706#!/compare/1492214400/1492300800

10.5 + 0.7 = 11.2, which rounds to 11 Keys

Sale 3) Sold for a Circling Peace Sign Tippler's Tricorne

http://backpack.tf/profiles/76561198085833195#!/compare/1493424000/1493510400

That was last priced almost 2 years ago, so this sale would probably be better used to price that.

http://backpack.tf/item/1697617695

Sale 4) Sold for a Smoking Carouser's Capotain

http://backpack.tf/profiles/76561198126521438#!/compare/1490918400/1491004800

If it's 9 Keys, then the Classified Buyers rule this sale low. I doubt it's higher than 11 Keys.

Sale 5) Sold for 11 Keys

http://backpack.tf/profiles/76561198248383364#!/compare/1491004800/1491091200 - Buyer's Backpack

I checked all of the histories. They match.