sale #1 - untrace

https://backpack.tf/profiles/76561198080179568#!/compare/1585785600/1585872000

https://backpack.tf/profiles/76561198340773732#!/compare/1585785600/1585872000

sale #2 - 9 keys

https://backpack.tf/profiles/76561198080179568#!/compare/1585872000/1585958400

https://backpack.tf/profiles/76561198019497121#!/compare/1585094400/1585958400

sale #3 - 7 keys + ref

https://backpack.tf/profiles/76561198257798400#!/compare/1581033600/1581120000

https://backpack.tf/profiles/76561198057124378#!/compare/1580947200/1581033600

sale #4 - 11 keys

https://backpack.tf/profiles/76561198057124378#!/compare/1585440000/1585526400

https://backpack.tf/profiles/76561198165074941#!/compare/1579478400/1585699200

sale #5 - bulk

https://backpack.tf/profiles/76561198088409405#!/compare/1581811200/1581724800

https://backpack.tf/profiles/76561198154023527#!/compare/1581724800/1581811200

sale #6 - use there

https://backpack.tf/profiles/76561198154023527#!/compare/1582329600/1582502400

https://backpack.tf/profiles/76561198335095206#!/compare/1582416000/1582502400

sale #7 - bulk

https://backpack.tf/profiles/76561198337734785#!/compare/1582761600/1582848000

https://backpack.tf/profiles/76561198335095206#!/compare/1582761600/1582848000

sale #8 - untrace

https://backpack.tf/profiles/76561198337734785#!/compare/1583020800/1583107200

https://backpack.tf/profiles/76561198152773135#!/compare/1582329600/1584057600

sale #9 - bulk

https://backpack.tf/profiles/76561198152773135#!/compare/1584057600/1584662400

https://backpack.tf/profiles/76561198252999692#!/compare/1584576000/1584662400

sale #10 - use there

https://backpack.tf/profiles/76561198395318833#!/compare/1584489600/1584662400

https://backpack.tf/profiles/76561198252999692#!/compare/1584576000/1584662400

sale #11 + 12 - https://marketplace.tf/items/tf2/109;5;u33 | no clue on history | no clue on b/o

$22.99 / $1.75 = 13.14 keys

$19.99 / $1.77 = 11.29 keys

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Given the unsold @ 12, ima exclude it - https://gyazo.com/a01d68961f9ddf9d5033c5e985519d8c

Taking 9 - 11 keys

excluding 7 due to buyers