Sale 1:

https://backpack.tf/profiles/76561198151087213#!/compare/1570579200/1570665600

https://backpack.tf/profiles/76561198341171690#!/compare/1570579200/1570665600

Sold for ~6 keys (QS)

Sale 2:

https://backpack.tf/profiles/76561198153833965#!/compare/1568246400/1568332800

https://backpack.tf/profiles/76561198323565601#!/compare/1568246400/1568332800

QS

sale 3:

https://backpack.tf/profiles/76561198411969284#!/compare/1566000000/1566172800

https://backpack.tf/profiles/76561198418909998#!/compare/1567641600/1569974400

Untrace

Sale 4:

https://backpack.tf/profiles/76561198799036690#!/compare/1564012800/1564185600

https://backpack.tf/profiles/76561197996869097#!/compare/1564185600/1564272000

Untrace

Sale 5:

https://backpack.tf/profiles/76561198104069164#!/compare/1567987200/1568246400

https://backpack.tf/profiles/76561198323565601#!/compare/1568073600/1568160000

QS

sale 6:

https://backpack.tf/profiles/76561198325261992#!/compare/1568851200/1568937600

https://backpack.tf/profiles/76561198378787341#!/compare/1568851200/1568937600

Untrace...

Sale 7:

https://backpack.tf/profiles/76561198378787341#!/compare/1568851200/1568937600

https://backpack.tf/profiles/76561198323565601#!/compare/1568851200/1568937600

QS

Sale 8:

https://backpack.tf/profiles/76561198062456002#!/compare/1555027200/1568246400

https://backpack.tf/profiles/76561198121830870#!/compare/1568160000/1568246400

Untrace, probably QS

Sale 9:

https://backpack.tf/profiles/76561198121830870#!/compare/1569110400/1569196800

https://backpack.tf/profiles/76561198393426246#!/compare/1569196800/1569283200

https://backpack.tf/profiles/76561198129380689#!/compare/1569196800/1569283200

Untrace

Sale 10:

https://backpack.tf/profiles/76561198129380689#!/compare/1569196800/1569283200

https://backpack.tf/profiles/76561198154700747#!/compare/1569196800/1569283200

Sold for 6 keys

Sale 11:

https://backpack.tf/profiles/76561198129361450#!/compare/1567641600/1569715200

https://backpack.tf/profiles/76561198121830870#!/compare/1568332800/1568419200

QS

Sale 12:

https://backpack.tf/profiles/76561198063803737#!/compare/1568937600/1569024000

https://backpack.tf/profiles/76561198372681544#!/compare/1568851200/1568937600

Untrace / Bulk

Sale 13:

https://backpack.tf/profiles/76561198089253101#!/compare/1566518400/1566604800

https://backpack.tf/profiles/76561198855785526#!/compare/1566518400/1566604800

Sold for OF Tailor

use there

sale 14:

https://backpack.tf/profiles/76561198855785526#!/compare/1567728000/1567814400

https://backpack.tf/profiles/76561198340634356#!/compare/1567641600/1567728000

QS

Sale 15:

https://backpack.tf/profiles/76561198340634356#!/compare/1569110400/1569196800

https://backpack.tf/profiles/76561198312583107#!/compare/1569110400/1569196800

Bulk

sale 16:

https://marketplace.tf/items/tf2/30042;5;u60

$14.39 / $1.84 = 7.82 keys <-- https://backpack.tf/item/1794848012

$14.39 / $1.84 = 7.82 keys

$12.95 / $1.82 = 7.12 keys

$12.95 / $1.82 = 7.12 keys <-- https://backpack.tf/item/7956008343

$12.75 / $1.82 = 7.01 keys

Total sales @:

6, 6, 7, 7, 7, 8, 8 keys

2 sellers for 7 keys, 1 unsold for ~2 weeks,

buyers up to 6 keys,

calling 2 outliers on both ends,

taking 7 flat.