Rudolph the red nose reindeer

Sale 1

http://www.tf2outpost.com/trade/24876191

Sold with smoking birdcage and ~4.7 keys in items for bubbling skullcap

http://backpack.tf/profiles/76561198135402633?time=1423296000 -> http://backpack.tf/profiles/76561198135402633?time=1423549403

(10/12.5+ 4.7/12.5 + X)*0.9 = 4.25

X= 3.54622.. (3.5)

Mini for birdcage

http://www.tf2outpost.com/trade/25039001

Sold for 10 keys pure

http://backpack.tf/profiles/76561198114800338?time=1424592000 -> http://backpack.tf/profiles/76561198114800338?time=1424701313

Sale 2

http://www.tf2outpost.com/trade/24178098

Sold with smoking birdcage (again) and sf buff banner for Duped Knifestorm waxy

http://backpack.tf/profiles/76561197960699801?time=1422950400 -> http://backpack.tf/profiles/76561197960699801?time=1423209600

(10/12.5 + 3.5/12.5 + X) * 0.9 = 3.1

X = 2.364 (2.4)

Mini for Waxy

Sold with 7 keys + #58 pocket raiders for DaD Gonzilla

http://www.tf2outpost.com/trade/24832934

http://backpack.tf/profiles/76561198071756409?time=1422766018 -> http://backpack.tf/profiles/76561198071756409?time=1422777600

(X + 1.9/12.5)*0.9 + 7/12.5 = 3.5

X = 3.114 (3.1)

Mini for raiders (Credits to Charles for the screenshots)

Sold with dbd bubble + 7 keys for planets.Exe

http://i.imgur.com/ajohwIU.png

http://i.imgur.com/kHkF4Bh.png

http://i.imgur.com/c7CWDDY.png

(2.95 + X/12.5)*0.9 +7/12.5 = 3.35

X = 1.85 (1.9)

Feel free to support/counter my proof