Sale 1:

https://backpack.tf/profiles/76561198044217834#!/compare/1582329600/1582934400

https://backpack.tf/profiles/76561198324700619#!/compare/1582848000/1582934400

Bulk

sale 2:

https://backpack.tf/profiles/76561198324700619#!/compare/1583107200/1583193600

https://backpack.tf/profiles/76561198204863571#!/compare/1583107200/1583193600

QS

sale 3:

https://backpack.tf/profiles/76561198024694313#!/compare/1583280000/1583452800

https://backpack.tf/profiles/76561198856199480#!/compare/1584403200/1584403200

Untrace

sale 4:

https://backpack.tf/profiles/76561198799074805#!/compare/1585612800/1587081600

https://backpack.tf/profiles/76561198866514793#!/compare/1586822400/1586995200

Bulk

sale 5:

https://backpack.tf/profiles/76561198024694313#!/compare/1582761600/1582934400

https://backpack.tf/profiles/76561198362648729#!/compare/1583366400/1587340800

Untrace

sale 6:

https://backpack.tf/profiles/76561198355490842#!/compare/1582243200/1582329600

https://backpack.tf/profiles/76561198346600524#!/compare/1583539200/1583798400

Untrace

sale 7:

https://backpack.tf/profiles/76561198346600524#!/compare/1583798400/1583884800

https://backpack.tf/profiles/76561198850667361#!/compare/1583712000/1583798400

Untrace

sale 8:

https://backpack.tf/profiles/76561198850667361#!/compare/1583798400/1584057600

https://backpack.tf/profiles/76561198019221999#!/compare/1580256000/1585699200

Untrace

Sale 9:

https://backpack.tf/profiles/76561198040220388#!/compare/1584057600/1584144000

https://backpack.tf/profiles/76561198100879076#!/compare/1584057600/1584316800

not unusual during trade(?)

Sale 10:

https://backpack.tf/profiles/76561198838447026#!/compare/1582588800/1582675200

https://backpack.tf/profiles/76561198974289370#!/compare/1582588800/1582761600

Bulk

sale 11:

https://backpack.tf/profiles/76561198974289370#!/compare/1583193600/1583280000

https://backpack.tf/profiles/76561198037674114#!/compare/1583107200/1583884800

untrace

sale 12:

https://backpack.tf/profiles/76561198037674114#!/compare/1583884800/1583107200

https://backpack.tf/profiles/76561198204863571#!/compare/1584230400/1584316800

QS

sale 13:

https://backpack.tf/profiles/76561198204863571#!/compare/1584230400/1584316800

https://backpack.tf/profiles/76561198162153971#!/compare/1489968000/1586822400

Untrace

sale 14:

https://backpack.tf/profiles/76561198216806363#!/compare/1581552000/1587600000

https://backpack.tf/profiles/76561198334598690#!/compare/1581465600/1581552000

QS

sale 15:

https://marketplace.tf/items/tf2/1120;5;u3009

$7.9 / $1.79 = 4.41 keys

$5.1 / $1.77 = 2.88 keys <--- https://backpack.tf/item/2774160500

Bot.tf:

1 @ 3 keys

1 @ 3.38 keys,

1 @ 4 keys

1 @ 2.79 keys,

Total sales @:

2.80, 2.90, 3, 3.40, 4, 4.40 keys

buyers up to ~3.20 keys,

new seller for ~3.48 keys,

note that buyer at 3.2 is much higher than other universal buyers,

taking 3.4 - 4.4 keys, for now.