Sale 1:

untrace

https://backpack.tf/profiles/76561198153081613#!/compare/1568764800/1569110400

https://backpack.tf/profiles/76561198405494620#!/compare/1568332800/1569801600

Sale 2:

6 keys + 16 ref

https://backpack.tf/profiles/76561198073176682#!/compare/1568764800/1568851200

https://backpack.tf/profiles/76561198050518375#!/compare/1568764800/1568851200

Sale 3:

8 keys

https://backpack.tf/profiles/76561198086846963#!/compare/1566691200/1566950400

https://backpack.tf/profiles/76561198874815681#!/compare/1566777600/1566864000

Sale 4:

untrace, but probably 8 keys

https://backpack.tf/profiles/76561198086846963#!/compare/1567382400/1567728000

https://backpack.tf/profiles/76561198062205682#!/compare/1567296000/1567382400

Sale 5:

Killstreak Big Kill(7.5 keys)

https://backpack.tf/profiles/76561198062205682#!/compare/1567296000/1567382400

https://backpack.tf/profiles/76561198174685127#!/compare/1567296000/1567382400

big kill: https://imgur.com/a/xScQKtr

Sale 6:

8 keys

https://backpack.tf/profiles/76561198174685127#!/compare/1567641600/1567728000

https://backpack.tf/profiles/76561198162548251#!/compare/1567641600/1567728000

Sale 7:

6 keys? there were perhaps more keys involved that were then used to buy the bills

https://backpack.tf/profiles/76561198051726874#!/compare/1569542400/1569628800

https://backpack.tf/profiles/76561198094964657#!/compare/1569542400/1569628800

Sale 8:

untrace

https://backpack.tf/profiles/76561198094964657#!/compare/1570406400/1570492800

https://backpack.tf/profiles/76561198032538711#!/compare/1569974400/1570752000

Sale 9:

Dead Presidents Stout Shako(8 keys)

https://backpack.tf/profiles/76561198032538711#!/compare/1570752000/1571702400

https://backpack.tf/profiles/76561198148232962#!/compare/1571270400/1571356800

Shako: https://backpack.tf/suggestion/5dd4770167807212ae7bf245

Sale 10:

untrace

https://backpack.tf/profiles/76561198148232962#!/compare/1571270400/1571356800

https://backpack.tf/profiles/76561198986498652#!/compare/1571184000/1571356800

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

Sales:

2x 6 keys

1x 7.5 keys

4x 8 keys

Buyers at 6.3 keys: https://imgur.com/a/rx61tEy