Sale 1:

https://backpack.tf/profiles/76561198032708322#!/compare/1577318400/1578441600

https://backpack.tf/profiles/76561198140316312#!/compare/1578009600/1578441600

Bulk

Sale 2:

https://backpack.tf/profiles/76561198140316312#!/compare/1579219200/1579305600

https://backpack.tf/profiles/76561199013116388#!/compare/1579132800/1579305600

Bulk

Sale 3:

https://backpack.tf/profiles/76561199013116388#!/compare/1579392000/1579564800

https://backpack.tf/profiles/76561198400462154#!/compare/1579046400/1579910400

Bulk

Sale 4:

https://backpack.tf/profiles/76561198331398297#!/compare/1578441600/1578528000

https://backpack.tf/profiles/76561198066566813#!/compare/1578441600/1578528000

Bulk

Sale 5:

https://backpack.tf/profiles/76561198066566813#!/compare/1579392000/1579478400

https://backpack.tf/profiles/76561198195741163#!/compare/1579392000/1579478400

Untrace

Sale 6:

https://backpack.tf/profiles/76561198314211872#!/compare/1580169600/1580256000

https://backpack.tf/profiles/76561198218784429#!/compare/1580169600/1580256000

Sold for 4 keys

Sale 7:

https://backpack.tf/profiles/76561198118911569#!/compare/1578873600/1579046400

https://backpack.tf/profiles/76561198838447026#!/compare/1578960000/1579046400

QS(?)

Sale 8:

https://backpack.tf/profiles/76561198838447026#!/compare/1579564800/1579651200

https://backpack.tf/profiles/76561198280158485#!/compare/1579132800/1580515200

Untrace

Sale 9:

https://backpack.tf/profiles/76561198083764840#!/compare/1576368000/1576454400

https://backpack.tf/profiles/76561198092437483#!/compare/1574553600/1579046400

Untrace

Sale 10 - 15:

https://marketplace.tf/items/tf2/1182;5;u3030

$8 / $1.77 = 4.52 keys <---- https://backpack.tf/item/6252999384

$7 / $1.80 = 3.89 keys <--- https://backpack.tf/item/6449464770

$7 / $1.78 = 3.93 keys <--- https://backpack.tf/item/6424505417

$7 / $1.78 = 3.93 keys

$7 / $1.78 = 3.93 keys

$7.95 / $1.76 = 4.52 keys

Total sales @:

4, 4, 4, 4, 4, 4.5, 4.5 keys

taking 4 - 4.5 keys