Meh.

Sale 1

http://www.tf2outpost.com/trade/25753848 - Sold for 4 keys + 10 keys in items (4 + 10*0.9 = 13 keys)

Sale 2

Before: http://backpack.tf/profiles/76561198121942187?time=1427852058

After: http://backpack.tf/profiles/76561198121942187?time=1427871600

- Sold for a Painted Law (1 key) + Strange Professional Killstreak Silver Botkiller Knife Mk.II (10 keys) (11*0.9 = 10 keys)

Sale 3

http://www.tf2outpost.com/trade/25486212 - Sold for a Strange Specialized Killstreak Rescue Ranger (1.5 keys) + Strange Professional Killstreak Bazaar Bargain (3 keys) + 4 keys in items (Outlier)

Sale 4

http://www.tf2outpost.com/trade/25740064 - Overpaid in items but BO of 10 keys

Feel free to counter / support my proofs