Sale 1:

https://backpack.tf/profiles/76561198850274253#!/compare/1586390400/1586476800

https://backpack.tf/profiles/76561198154620867#!/compare/1584921600/1586476800

Untrace / Bulk

sale 2:

https://backpack.tf/profiles/76561198203094121#!/compare/1585008000/1585180800

https://backpack.tf/profiles/76561198337734785#!/compare/1587254400/1587340800

QS

sale 3:

https://backpack.tf/profiles/76561198850274253#!/compare/1586390400/1586476800

https://backpack.tf/profiles/76561198826771573#!/compare/1585353600/1586476800

Bulk

sale 4:

https://backpack.tf/profiles/76561198826771573#!/compare/1586476800/1586995200

https://backpack.tf/profiles/76561198986747837#!/compare/1586476800/1586563200

Untrace

sale 5:

https://backpack.tf/profiles/76561198080179568#!/compare/1586563200/1586649600

https://backpack.tf/profiles/76561198257516365#!/compare/1586649600/1587081600

Sold for 6 keys

sale 6:

https://backpack.tf/profiles/76561198129396206#!/compare/1587772800/1587859200

https://backpack.tf/profiles/76561198987674719#!/compare/1587772800/1587859200

Sold with negligible sweets for 6 keys

sale 7:

https://backpack.tf/profiles/76561198987674719#!/compare/1587859200/1587945600

https://backpack.tf/profiles/76561198254204805#!/compare/1587859200/1587945600

Untrace

sale 8:

https://backpack.tf/profiles/76561198254204805#!/compare/1587945600/1588032000

https://backpack.tf/profiles/76561198137163870#!/compare/1587859200/1587945600

Untrace

sale 9:

https://backpack.tf/profiles/76561198137163870#!/compare/1587859200/1587945600

https://backpack.tf/profiles/76561198320329443#!/compare/1587859200/1587945600

Untrace

Sale 10:

https://backpack.tf/profiles/76561198320329443#!/compare/1587945600/1588032000

https://backpack.tf/profiles/76561198310700218#!/compare/1587427200/1588204800

Sold for Aces Plug-In(~6.5)

sale 11:

https://backpack.tf/profiles/76561198101398885#!/compare/1590364800/1590451200

https://backpack.tf/profiles/76561199053800917#!/compare/1590364800/1590451200

Bulk

sale 12:

https://backpack.tf/profiles/76561199053800917#!/compare/1590364800/1590451200

https://backpack.tf/profiles/76561198435061144#!/compare/1590451200/1590278400

https://backpack.tf/profiles/76561199053800917#!/compare/1590451200/1590537600

https://backpack.tf/profiles/76561198435061144#!/compare/1590451200/1590537600

transfers

sale 13:

https://backpack.tf/profiles/76561198080179568#!/compare/1585612800/1585699200

https://backpack.tf/profiles/76561198130923675#!/compare/1585267200/1585785600

Sold for 6 keys

sale 14:

https://backpack.tf/profiles/76561198130923675#!/compare/1585872000/1586044800

https://backpack.tf/profiles/76561198295486957#!/compare/1585872000/1585958400

https://backpack.tf/profiles/76561198114796991#!/compare/1586390400/1586476800

https://backpack.tf/profiles/76561198986747837#!/compare/1586390400/1586476800

https://backpack.tf/profiles/76561198061694931#!/compare/1586390400/1586476800

https://backpack.tf/profiles/76561198139422167#!/compare/1567987200/1588291200

Untrace / bulk

sale 15:

https://backpack.tf/profiles/76561198048851745#!/compare/1587772800/1587859200

https://backpack.tf/profiles/76561198062805422#!/compare/1587772800/1587859200

Sold for ~6 keys

sale 16:

https://backpack.tf/profiles/76561198062805422#!/compare/1588032000/1588118400

https://backpack.tf/profiles/76561198817843697#!/compare/1588032000/1588118400

QS

sale 17:

https://backpack.tf/profiles/76561198817843697#!/compare/1588118400/1588204800

https://backpack.tf/profiles/76561198396499936#!/compare/1588118400/1588204800

Keys

sale 18:

https://backpack.tf/profiles/76561198396499936#!/compare/1588896000/1588982400

https://backpack.tf/profiles/76561198169455952#!/compare/1588896000/1588982400

Sold for Bubbling Commando

use there

sale 19:

https://marketplace.tf/items/tf2/363;5;u59

$12.49 / $1.68 = 7.43 keys <--- https://backpack.tf/item/7955745054

$12.49 / $1.70 = 7.35 keys

$11.49 / $1.69 = 6.80 keys

$12.99 / $1.79 = 7.26 keys

Total sales @:

6, 6, 6, 6, 6.5, 7, 7.5, 7.5, 7.5 keys

buyers up to ~5.89 keys,

https://i.imgur.com/c1rjzUK.jpg

https://i.imgur.com/98BfcHU.jpg

sellers for ~7 keys, new / aging,

one recently dropped from ~8 keys,

taking 6 - 7.5 keys, no good reason i can see to exclude any sale.