Sale 1:

Sold for Aces High Burning Beanie (14) + 2 keys

No outpost

Seller: https://backpack.tf/profiles/76561198403777524#!/compare/1532390400/1532476800

Buyer: https://backpack.tf/profiles/76561198176020335#!/compare/1532304000/1532476800

https://backpack.tf/item/5995646580

X = 16

Sale 2:

Sold for 15 keys

Seller: https://backpack.tf/profiles/76561197999873164#!/compare/1535328000/1535414400

Buyer: https://backpack.tf/profiles/76561198095560349#!/compare/1535328000/1535414400

https://backpack.tf/item/4984509093

X = 15

Sale 3:

Sold for 14 keys

Seller: https://backpack.tf/profiles/76561198042938501#!/compare/1530403200/1530489600

Buyer: https://backpack.tf/profiles/76561198001229964#!/compare/1530316800/1531008000

https://backpack.tf/item/5804333257

X = 14

Sale 4:

Sold for 13 keys + 2 ref

Seller: https://backpack.tf/profiles/76561198098536989#!/compare/1534550400/1534636800

Buyer: https://backpack.tf/profiles/76561198090671680#!/compare/1534377600/1534636800

https://backpack.tf/item/5007854201

X = 13

Sale 5:

Sold for 13 keys

Seller: https://backpack.tf/profiles/76561198820728761#!/compare/1536451200/1536537600

Buyer: https://backpack.tf/profiles/76561198103971429#!/compare/1536451200/1536537600

https://backpack.tf/item/7010603527

X = 13

Sale 6:

Sold for 13 keys

Seller: https://backpack.tf/profiles/76561198103971429#!/compare/1536537600/1536624000

Buyer: https://backpack.tf/profiles/76561198103051760#!/compare/1536537600/1536624000

https://backpack.tf/item/7010603527

X = 13

Sale 7:

Sold for 13 keys

Seller: https://backpack.tf/profiles/76561198096237015#!/compare/1534291200/1534377600

Buyer: https://backpack.tf/profiles/76561198057095016#!/compare/1533081600/1534377600

https://backpack.tf/item/5596646733

X = 13

Sale 8:

Sold to a bot for 12 keys + 20.33 ref

Seller: https://backpack.tf/profiles/76561198231092000#!/compare/1535673600/1535760000

Buyer: https://backpack.tf/profiles/76561198515764827#!/compare/1535587200/1535760000

https://i.imgur.com/GpTEI5p.png

X = 13

Sale 9:

Sold for 12 keys + 1 ref

Seller: https://backpack.tf/profiles/76561198046960638#!/compare/1529712000/1529798400

Buyer: https://backpack.tf/profiles/76561197995029705#!/compare/1529798400/1529884800

X = 12

Sale 10:

Sold for 12 keys

Seller: https://backpack.tf/profiles/76561198090671680#!/compare/1534723200/1535155200

Buyer: https://backpack.tf/profiles/76561198231092000#!/compare/1535068800/1535155200

https://backpack.tf/item/5007854201

X = 12

Sale 11:

Sold for Orbiting Planets Hat With No Name

No outpost

Seller: https://backpack.tf/profiles/76561198176020335#!/compare/1533945600/1534032000

Buyer: https://backpack.tf/profiles/76561198281102963#!/compare/1533945600/1534032000

https://backpack.tf/item/5995646580

Most likely an outlier here.

Other Sales:

https://backpack.tf/item/7010603527 (#1-3)

https://backpack.tf/item/5995646580 (#4-8)

https://backpack.tf/item/5804333257 (#9)

https://backpack.tf/item/5697259243 (#10 & 11, other sale here was from bot to bot owner)

https://backpack.tf/item/5596646733 (#12-14)

https://backpack.tf/item/5007854201 (#15)

https://backpack.tf/item/4818246916 (#16)

https://backpack.tf/item/6985492497 - tradeit stuff.

#1

Untraceable, sold to scrap.tf

https://backpack.tf/profiles/76561198180529062 - rate limit exceeded, can’t access it lol

#2

Untraceable, bought from scrap.tf

https://backpack.tf/profiles/76561198135388328#!/compare/1536364800/1536451200

https://backpack.tf/profiles/76561198820728761#!/compare/1536451200/1536537600

#3

Untraceable

https://backpack.tf/profiles/76561198103051760#!/compare/1536537600/1536624000

https://backpack.tf/profiles/76561198401509004#!/compare/1536451200/1536537600

#4

Sold for Cloud 9 Airdog

https://backpack.tf/profiles/76561198128953533#!/compare/1531958400/1532044800

https://backpack.tf/profiles/76561198218628708#!/compare/1531958400/1532044800

#5

Bulk for Terror-Watt Tyrant’s Helm

https://backpack.tf/profiles/76561198218628708#!/compare/1532044800/1532131200

https://backpack.tf/profiles/76561198122057139#!/compare/1532044800/1532131200

#6

Sold with cheap items for Stormy Storm Surgeon’s Stahlhelm

https://backpack.tf/profiles/76561198122057139#!/compare/1532390400/1532476800

https://backpack.tf/profiles/76561198403777524#!/compare/1532390400/1532476800

No B/O

Seems pretty high, might be better to exclude this one entirely.

#7

Sold for Vivid Plasma Bomb Beanie

https://backpack.tf/profiles/76561198281102963#!/compare/1533945600/1534032000

https://backpack.tf/profiles/76561198280868306#!/compare/1533859200/1534032000

#8

Untraceable

https://backpack.tf/profiles/76561198280868306#!/compare/1534118400/1535760000

https://backpack.tf/profiles/76561198337734785#!/compare/1534032000/1534118400

#9

Untraceable

https://backpack.tf/profiles/76561197995029705#!/compare/1530230400/1530316800

https://backpack.tf/profiles/76561198042938501#!/compare/1530057600/1530316800

#10

Untraceable

https://backpack.tf/profiles/76561198385940902#!/compare/1530403200/1530489600

https://backpack.tf/profiles/76561198352738720#!/compare/1530403200/1530489600

https://i.imgur.com/GpTEI5p.png - labelled as 17 keys

#11

Untraceable

https://backpack.tf/profiles/76561198352738720#!/compare/1530748800/1531180800

https://backpack.tf/profiles/76561198385940902#!/compare/1530835200/1530921600

https://i.imgur.com/GpTEI5p.png - Labelled as 12 keys + 20 ref

#12

Untraceable

https://backpack.tf/profiles/76561198129477361

https://backpack.tf/profiles/76561198096237015#!/compare/1533340800/1534291200

Seller’s backpack is private.

#13

Sold for 4 ref

https://backpack.tf/profiles/76561198057095016#!/compare/1533081600/1534377600

https://backpack.tf/profiles/76561198079084361#!/compare/1534204800/1534377600

or just untraceable.

#14

Sold to unscanned backpack, then dumped on scrap.tf

https://backpack.tf/profiles/76561197999873164#!/compare/1533254400/1533340800

#15

Untraceable, bought from scrap.tf

https://backpack.tf/profiles/76561198135388328#!/compare/1534550400/1534636800

https://backpack.tf/profiles/76561198098536989#!/compare/1534550400/1534636800

#16

Untraceable

https://backpack.tf/profiles/76561198035450661#!/compare/1533254400/1533340800

https://backpack.tf/profiles/76561198337734785#!/compare/1533254400/1533340800

Sellers:

https://i.imgur.com/nl8tzs2.png

https://backpack.tf/item/7010603527 - 14 keys

https://backpack.tf/item/6985492497 - ~14.87 keys

https://backpack.tf/item/5007854201 - 15 keys

https://backpack.tf/item/5697259243 - 15 keys

Sales at:

12 (2x)

13 (5x)

14

15

16

Buyers at 12+

https://i.imgur.com/Q2dVQwu.png

Excluding 12.

16 is an outlier given the cheaper sellers. Excluding 16.

Going with 13-15.