Play your cards.

https://backpack.tf/item/4835260217

Sale 1) Sold for a Smoking Das Ubersternmann

https://backpack.tf/profiles/76561198258264645#!/compare/1501200000/1501372800

I was told by Mindacos not to use this sale.

Sale 2) Sold + 3 Keys for a Vivid Plasma Sergeant's Drill Hat (35 Keys)

https://backpack.tf/profiles/76561198074181346#!/compare/1501545600/1501632000 - Seller's Backpack

https://backpack.tf/profiles/76561198267189538#!/compare/1501545600/1501632000 - Buyer's Backpack

35 - 3 = 32 Keys

Drill Mini

https://backpack.tf/suggestion/59aa145acf6c75314e1b465a - 35 Keys

Sale 3) Quicksold for 27 Keys

https://backpack.tf/profiles/76561198267189538#!/compare/1501545600/1501632000

The other 1 Key + 3.33 Refined was not involved.

Sale 4) Quicksold for 27 Keys

https://backpack.tf/profiles/76561198309937181#!/compare/1501632000/1501718400

Sale 5) Quicksold for 27 Keys + 18 Refined

https://backpack.tf/profiles/76561198109272505#!/compare/1501632000/1501718400

Sale 6) Sold for 30 Keys

https://backpack.tf/profiles/76561198136287595#!/compare/1502668800/1502928000 - Buyer's Backpack

https://backpack.tf/item/4642059228

Sale 7) Sold for 28 Keys

https://backpack.tf/profiles/76561198296168912#!/compare/1498521600/1498608000

Sale 8) Sold for a Smoking Frickin' Sweet Ninja Hood

https://backpack.tf/profiles/76561198225025568#!/compare/1498867200/1498953600

http://www.tf2outpost.com/trade/29249596 - Capped by the Buyout of 34 Keys

Sale 9) Sold for a Duped Cauldron Bubbles Lucky Shot (41 Keys)

https://backpack.tf/profiles/76561198074764837#!/compare/1499299200/1499385600

http://www.tf2outpost.com/trade/29257350 - Capped by the Buyout of 30 Keys

https://backpack.tf/item/4611081183

Sale 10) Sold + Steaming Wraith Wrap (19 Keys) + ~4 Keys of Items for a Terror-Watt Patriot Peak

https://backpack.tf/profiles/76561198068674577#!/compare/1499731200/1500076800

High Outlier.

Sale 11) Bulk sale for a bunch of Australiums

https://backpack.tf/profiles/76561198202135278#!/compare/1500163200/1500249600

Sale 12) Sold for a Tesla Coil Tough Guy's Toque + 7 Keys

https://backpack.tf/profiles/76561198072087574#!/compare/1501891200/1502236800

http://www.tf2outpost.com/trade/29306100 - Capped by the Buyout of 30 Keys?

Sale 13) Sold for a Purple Energy Pyro's Beanie (32 Keys)

https://backpack.tf/profiles/76561198101327173#!/compare/1503792000/1504224000

http://www.tf2outpost.com/trade/29343888 - Capped by the Buyout of 30 Keys

Using the 2 sales at 27 and the sale at roughly 27.5 to support 28 Keys being in the range.

Calling Sale 10 high because of this 1 Month Unsold at 39 Keys: http://imgur.com/a/LU8Jk