Sale 1-2:

https://marketplace.tf/items/tf2/1117;5;u3023

$6 / $1.79 = 3.35 keys

$4.06 / $1.77 = 2.29 keys

now under buy orders: https://imgur.com/a/sGU64Oo

Sale 3:

crafted, not a sale

https://backpack.tf/profiles/76561198155441223#!/compare/1570406400/1570752000

Sale 4:

with unsolds on bunnyhopper this will be under buy orders: https://imgur.com/a/sGU64Oo

Sold with 1 key skin for Screaming Tiger Bunnyhopper

https://backpack.tf/profiles/76561198237988170#!/compare/1571961600/1572134400

https://backpack.tf/profiles/76561198172882633#!/compare/1571529600/1572134400

Sale 5:

untrace

https://backpack.tf/profiles/76561198237988170#!/compare/1572566400/1572652800

https://backpack.tf/profiles/76561198101092551#!/compare/1572566400/1572652800

Sale 6:

even taking buy orders on CC this seems like high outlier

Sold with 1 key for DBD Cloud Crasher

https://backpack.tf/profiles/76561198101092551#!/compare/1572652800/1572739200

https://backpack.tf/profiles/76561198249078668#!/compare/1572652800/1572739200

Sale 7:

under buy orders: https://imgur.com/a/sGU64Oo

sold for ~5 in skins

https://backpack.tf/profiles/76561198056086416#!/compare/1572739200/1572825600

https://backpack.tf/profiles/76561198249078668#!/compare/1572739200/1572825600

Sale 8:

under buy orders: https://imgur.com/a/sGU64Oo

6 keys

https://backpack.tf/profiles/76561198112305692#!/compare/1572480000/1572566400

https://backpack.tf/profiles/76561198275530188#!/compare/1572480000/1572566400

Sale 9:

7 keys + 0.5 key sweets

https://backpack.tf/profiles/76561198275530188#!/compare/1572480000/1572566400

https://backpack.tf/profiles/76561198418740133#!/compare/1572480000/1572566400

Sale 10:

untrace

https://backpack.tf/profiles/76561198055621547#!/compare/1572652800/1572825600

https://backpack.tf/profiles/76561198061402527#!/compare/1572825600/1572912000

Sale 11:

7 keys

https://backpack.tf/profiles/76561198061402527#!/compare/1572825600/1572912000

https://backpack.tf/profiles/76561198283288464#!/compare/1572825600/1572912000

==============================================================================

Sales:

2,3,5,6,7,7.5