Meh.

Sale 1

http://www.tf2outpost.com/trade/26053244 - Sold for a Strange Disco Beat Down Big Chief (24*0.9 = 22 keys)

Sale 2

http://www.tf2outpost.com/trade/26050112 - Sold with a Strange Australium Medi Gun (25 keys) for a Strange Professional Killstreak Australium Scattergun (45 - 25 = 20 keys)

Sale 3

Before: http://backpack.tf/profiles/76561198097269518?time=1432968759

After: http://backpack.tf/profiles/76561198097269518?time=1432969200

- Sold with an Aces High Human Cannonball (18 keys) for a Strange Australium Sniper Rifle (34 keys) + 6 keys (40 - 18 = 22 keys)

Sale 4

Before: http://backpack.tf/profiles/76561198124336862?time=1431146212

After: http://backpack.tf/profiles/76561198124336862?time=1431241200

- Sold with 5 keys + 5 keys in sweets for a Miami Nights Reggaelator (31 - 10 = 21 keys)

Feel free to counter / support my proofs