Sale 1-6:

https://marketplace.tf/items/tf2/31003;5;u121

$35 / $1.81 = 19.34 keys

$35 / $1.82 = 19.23 keys

$36 / $1.82 = 19.78 keys

$36.99 / $1.83 = 20.21 keys

$49.18 / $1.81 = 27.17 keys

$26 / $1.78 = 14.6 keys

no histories really line up, could be any of these:

https://backpack.tf/item/7638717320

https://backpack.tf/item/7258745396

https://backpack.tf/item/7246428466

Sale 7:

untrace

https://backpack.tf/profiles/76561198363395191#!/compare/1566345600/1566432000

https://backpack.tf/profiles/76561198820175606#!/compare/1566345600/1566432000

Sale 8:

SCM

https://backpack.tf/profiles/76561198985469595#!/compare/1570752000/1571356800

https://backpack.tf/profiles/76561198238019026#!/compare/1566691200/1571184000

Sale 9:

untrace

https://backpack.tf/profiles/76561198074763279#!/compare/1567987200/1572220800

other side private bp

Sale 10:

rounding to 12 keys

11 keys + 30 ref

https://backpack.tf/profiles/76561198090418844#!/compare/1564963200/1565222400

https://backpack.tf/profiles/76561198066782948#!/compare/1565136000/1565222400

Sale 11:

11 keys

https://backpack.tf/profiles/76561198107839402#!/compare/1565136000/1565308800

https://backpack.tf/profiles/76561198066782948#!/compare/1565222400/1565308800

Sale 12:

rounding to 11 keys

Cloud 9 Powdered Practitioner(10.5 keys)

b/o was 13 keys: https://imgur.com/a/0fOGhPA

https://backpack.tf/profiles/76561198107839402#!/compare/1566259200/1566345600

https://backpack.tf/profiles/76561198263665713#!/compare/1566172800/1566432000

Practitioner: https://backpack.tf/suggestion/5db8e225d38172393b3349e2

Sale 13:

SCM

https://backpack.tf/profiles/76561198145460851#!/compare/1569369600/1569974400

other side doesnt load

Sale 14:

12 keys

https://backpack.tf/profiles/76561198212715087#!/compare/1567296000/1567382400

https://backpack.tf/profiles/76561198251978870#!/compare/1567209600/1567382400

Sale 15:

spelled hat? no mini

https://backpack.tf/profiles/76561198212715087#!/compare/1567468800/1567555200

https://backpack.tf/profiles/76561198135492876#!/compare/1567468800/1567555200

Sale 16:

9 keys

https://backpack.tf/profiles/76561198135492876#!/compare/1567468800/1567555200

https://backpack.tf/profiles/76561198035109737#!/compare/1567468800/1567555200

Sale 17:

untrace

https://backpack.tf/profiles/76561198083937853#!/compare/1571702400/1572048000

https://backpack.tf/profiles/76561198012537041#!/compare/1571788800/1571875200

Sale 18:

untrace

https://backpack.tf/profiles/76561198189106033#!/compare/1571875200/1571961600

https://backpack.tf/profiles/76561198012537041#!/compare/1571875200/1571961600

Sale 19:

untrace

https://backpack.tf/profiles/76561198189106033#!/compare/1571961600/1572048000

https://backpack.tf/profiles/76561198978221405#!/compare/1572048000/1572220800

Sale 20:

cant price bat hat yet, use on bat hat ig

https://backpack.tf/profiles/76561198243196922#!/compare/1571961600/1572048000

https://backpack.tf/profiles/76561198331167728#!/compare/1571788800/1572048000

Sale 21:

11 keys

with 8 keys for max head(19 keys)

max head(18.5-19.5): https://imgur.com/a/ktZQciE

https://backpack.tf/profiles/76561198331167728#!/compare/1572048000/1572307200

https://backpack.tf/profiles/76561198040585908#!/compare/1572220800/1572307200

Sale 22:

SCM

https://backpack.tf/profiles/76561198067308685#!/compare/1566432000/1567123200

https://backpack.tf/profiles/76561198076881692#!/compare/1566345600/1566691200

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

Sales:

9,11,11,11,12,12,15,19,19,20,20,27

mp buyers at around 14 keys: https://imgur.com/a/pGpiURr

excluding 27 as high outlier