Sale 1:

https://backpack.tf/profiles/76561198061426538#!/compare/1551744000/1552435200

https://backpack.tf/profiles/76561198275889110#!/compare/1552348800/1552435200

https://backpack.tf/profiles/76561198205415264#!/compare/1552953600/1553040000

Untrace / SCM

Sale 2:

https://backpack.tf/profiles/76561198116110446#!/compare/1555632000/1555891200

https://backpack.tf/profiles/76561198154268023#!/compare/1556323200/1556409600

SCM

Sale 3:

https://backpack.tf/profiles/76561198840456991#!/compare/1549756800/1550102400

https://backpack.tf/profiles/76561198227657840#!/compare/1549929600/1550102400

SCM

Sale 4:

https://backpack.tf/profiles/76561198227657840#!/compare/1552003200/1552089600

https://backpack.tf/profiles/76561198841279602#!/compare/1552003200/1552089600

Sold for ~5.5 keys

sale 5:

https://backpack.tf/profiles/76561198841279602#!/compare/1553558400/1553644800

https://backpack.tf/profiles/76561198449307015#!/compare/1553558400/1553644800

Sold for at least 5 keys... more prob involved.

Sale 6:

https://backpack.tf/profiles/76561198449307015#!/compare/1553731200/1553990400

https://backpack.tf/profiles/76561198354325293#!/compare/1552176000/1553990400

Sold for DP Mongolian

Mongolian Mini:

https://backpack.tf/suggestion/5cd52fbf6780723d97249c2c

Suggestion for 9 keys

Sale 7:

https://backpack.tf/profiles/76561198354325293#!/compare/1554940800/1555200000

https://backpack.tf/profiles/76561198044684270#!/compare/1554854400/1554940800

QS

Sale 8:

https://backpack.tf/item/5061095197

all of this was gambling / untrace / bulk.

Sale 9:

https://marketplace.tf/items/1119;5;u3015

$15.00 / $1.8 = 8.33 keys

Sale 10:

https://bot.tf/stats/item?def=1119&q=5&ef=Infernal%20Flames&craft=1&aus=0&ks=0

Sold for ~6.5 keys

Total sales @:

5.5, 6.5, 8.33, 9 keys

Buyers up to ~6.5 keys,

Taking 6.5 - 9 keys