Sale 1

25 keys. Spec. KS Black box +6 keys pure

Credit to Epic Wolf for the screenshot

http://imgur.com/8wstDIr

Seller

http://backpack.tf/profiles/76561197990986202?time=1447833600&compare=1447920000

Buyer

http://backpack.tf/profiles/76561198081057025?time=1447920000&compare=1447833600

Sale 2

Gifted hat Not using. Searing Plasma Hot Dogger [20 keys] plus 2 pure. 20*0.9 equals 18. 20 keys total

http://backpack.tf/profiles/76561198073623271?time=1441436400&compare=1441522800

Sale 3

Quick sale not using

18 keys. B/O was 19 keys.

http://backpack.tf/profiles/76561198130218075?time=1443942000&compare=1444028400

Sale 4

20 keys+ 4 ref in items. 20 keys

http://www.tf2outpost.com/trade/26854250

http://backpack.tf/profiles/76561198056793444?time=1441522800&compare=1441609200

Sale 5

Sold for max head 27 keys

http://backpack.tf/profiles/76561198044711708?time=1442386800&compare=1441609200

Sale 6

Sold for Terror-Watt Towering Pillar of Hats

http://backpack.tf/profiles/76561198127563863?time=1446361200&compare=1447056000

Mini for Pillar

Sale 1

http://backpack.tf/profiles/76561198127563863?time=1448006400&compare=1448179200

30.5-14.5

16 keys

Sale 2

Seller

http://backpack.tf/profiles/76561198061506886?time=1442041200&compare=1442214000

Buyer

http://backpack.tf/profiles/76561198061506886?time=1442041200&compare=1442214000

Pillar sold for The Ooze Respectless Robo-Glove + 2 keys in sweets

28.5*0.9 is 25.65 so 27 keys

Sale 3

Strange Killstreak Festive Sniper Rifle [14 keys] Genuine Shred Alert [1.8 keys] and 7 pure

16*.9 equals 14 keys plus 7. 21 keys

http://backpack.tf/profiles/76561198070883481?time=1443942000

http://backpack.tf/profiles/76561198070883481?time=1445151600

http://backpack.tf/profiles/76561198070883481?time=1443942000&compare=1445151600

So the range 16 to 27 gives 21.5 as the middle price and the actual price is 21

So I am taking 21 keys

Sale 7

Sold with sweets for Blizzardy Storm Your Worst Nightmare

Seller

http://backpack.tf/profiles/76561198208544995?time=1447315200&compare=1447401600

Buyer

http://backpack.tf/profiles/76561197990986202?time=1447228800&compare=1447315200

Mini for the Blizz Storm

http://backpack.tf/profiles/76561198151641635?time=1447056000&compare=1447142400

Sold with Bat Saber [10 keys] for Miami Nights Killer's Kabuto

28.2-10

18 keys

The sweets add to 4.49 keys

Credit to Rog for the screenshot

http://imgur.com/VzD63Dw

So 18-4.49 gives 13.5

14 keys on a good day. Taking it as outlier

Finally, my range will be 20 to 27 keys