Sale 1:

Sold for Strange Balloonihoodie (12.5) + 5 keys

No outpost

Seller: https://backpack.tf/profiles/76561198182795337#!/compare/1532131200/1532217600

Buyer: https://backpack.tf/profiles/76561198123225617#!/compare/1531872000/1532217600

https://backpack.tf/item/6751400878

X = 18

Sale 2:

Sold with ~1 key in items for Abduction Head Full of Hot Air (16)

http://www.tf2outpost.com/trade/29710222 - B/O of 16

Seller: https://backpack.tf/profiles/76561198116324749#!/compare/1531440000/1531526400

Buyer: https://backpack.tf/profiles/76561198067332644#!/compare/1531440000/1531526400

https://backpack.tf/item/6751400878

X = 15

Sale 3:

Sold for 14 keys

Seller: https://backpack.tf/profiles/76561198002757046#!/compare/1533600000/1533686400

Buyer: https://backpack.tf/profiles/76561198849723940#!/compare/1533600000/1533686400

https://backpack.tf/item/5743992145

X = 14

Sale 4:

Quicksold for 14 keys + some metal

Seller: https://backpack.tf/profiles/76561198074808151#!/compare/1530662400/1530748800

Buyer: https://backpack.tf/profiles/76561198116324749#!/compare/1530662400/1530748800

https://backpack.tf/item/6751400878

X = 14

Sale 5:

Sold for 13 keys + some ref

Seller: https://backpack.tf/profiles/76561198337734785#!/compare/1530576000/1530662400

Buyer: https://backpack.tf/profiles/76561198298677489#!/compare/1529798400/1530662400

https://backpack.tf/item/6751400878

X = 13

Other Sales:

#1

Untraceable, sold to scrap.tf

https://backpack.tf/profiles/76561198849723940#!/compare/1533686400/1535155200

https://backpack.tf/profiles/76561198135388328#!/compare/1533600000/1533686400

https://backpack.tf/item/5743992145

#2

Bulk for Searing Law

https://backpack.tf/profiles/76561198165941208#!/compare/1532390400/1532476800

https://backpack.tf/profiles/76561198314160142#!/compare/1532390400/1532476800

https://backpack.tf/item/2804576976

#3

Untraceable

https://backpack.tf/profiles/76561198314160142#!/compare/1532908800/1532995200

https://backpack.tf/profiles/76561198113922174#!/compare/1532908800/1532995200

https://backpack.tf/item/2804576976

#4

Bulk for Searing Plasma Full Metal Drill

https://backpack.tf/profiles/76561198059678425#!/compare/1532995200/1533081600

https://backpack.tf/profiles/76561198002757046#!/compare/1532995200/1533081600

https://backpack.tf/item/5743992145

#5

Sold for Bubbling Rebel Rouser

https://backpack.tf/profiles/76561198298677489#!/compare/1530662400/1530748800

https://backpack.tf/profiles/76561198074808151#!/compare/1530662400/1530748800

https://backpack.tf/item/6751400878

Can be used on the Rouser.

Sellers:

https://i.imgur.com/p58gWIB.png

https://backpack.tf/item/2804576976 - 14 keys

https://backpack.tf/item/2859087051 - 22 keys

And another on scrap for ~14.3 keys:

https://i.imgur.com/TyGpNB5.png

https://backpack.tf/item/5743992145

https://backpack.tf/profiles/76561198135388328#!/compare/1533600000/1533686400 - Obtained ~8th August

Sales at:

13

14 (2x)

15

18

18 is an outlier, excluding.

14 may have quicksold once, but we have 2 for sale at ~14 keys, so I’ll ignore that fact.

Going with 13-15.