Sale 1:

https://backpack.tf/profiles/76561198137179430#!/compare/1566777600/1566864000

https://backpack.tf/profiles/76561198326756661#!/compare/1566777600/1566864000

untrace

sale 2:

https://backpack.tf/profiles/76561198326756661#!/compare/1568073600/1568160000

https://backpack.tf/profiles/76561198377852582#!/compare/1568073600/1568246400

Sold for Aces Cosa

Cosa Mini:

https://backpack.tf/suggestion/5dca706e6780722ffb23dd03

Suggestion for 11.5 keys

Sale 3:

https://backpack.tf/profiles/76561198161047773#!/compare/1572393600/1573171200

https://backpack.tf/profiles/76561198026129220#!/compare/1572393600/1572480000

untrace

Sale 4 - 6:

https://marketplace.tf/items/tf2/30040;5;u57

$25.29 / $1.84 = 13.74 keys

$17 / $1.83 = 9.29 keys <--- https://backpack.tf/item/2222392200

$8 / $1.78 = 4.49 keys

Total sales @:

4.49, 9.29, 11.5, 13.74 keys

Mindacos' Part:

Unsold at $16.99 on marketplace. Normally I don't like to highlight these sellers as proper counter-proof, but maybe 14 is going to be on the high side of things?

Would make sense with how old the sale is now, I suppose.

taking 9 - 12 keys.