Sold for Non-Craftable Summer Hat (10) + Vintage Specialized Killstreak Lugermorph (7):

http://backpack.tf/profiles/76561198070235817?time=1420790400

http://www.tf2outpost.com/trade/24552943

http://www.tf2outpost.com/trade/24569672

http://backpack.tf/item/2017126081

(10 + 7) * .9 = 15.3 keys

Rounded to 15 keys

Sold for Stormy Storm Pyro's Beanie (1.3):

http://www.tf2outpost.com/trade/24552541

http://backpack.tf/profiles/76561198070235817?time=1420943948

Owner offered. ~19 keys

Sold with Smoking Shooter's Sola Topi (.88) for [Kill-a-Watt Stout Shako (2.2) + Strange Frying Pan (.62) + ~1.5 keys in sweets (.12)]:

http://backpack.tf/profiles/76561198054836343?time=1419848226

http://backpack.tf/profiles/76561198054836343?time=1419753600

(2.2 + .62 + .12) * .9 - .88 = 1.766 buds

Rounded to 1.8 buds. Outlier.

Sold for 17 keys:

http://www.tf2outpost.com/trade/23724134

http://backpack.tf/profiles/76561198070828047?time=1416211200

http://backpack.tf/profiles/76561198070828047?time=1420444800

Only 17 keys were tracked. 17 keys

Using keys as currency because most sellers had buyouts in keys.