Mini.

SALE 1

Seems like it was a unknown bulk sale, or a bulk scam :(

https://backpack.tf/profiles/76561198876179362#!/compare/1563408000/1565568000

https://backpack.tf/profiles/76561198378889905#!/compare/1565222400/1565308800

SALE 2

Unknown

https://backpack.tf/profiles/76561198043566764#!/compare/1563321600/1563667200

https://backpack.tf/profiles/76561198144462371#!/compare/1560470400/1565049600

SALE 3

Unknown

https://backpack.tf/profiles/76561198050933284#!/compare/1561334400/1562198400

https://backpack.tf/profiles/76561198043566764#!/compare/1561248000/1561334400

SALE 4

Unknown

https://backpack.tf/profiles/76561198114644154#!/compare/1564790400/1564876800

https://backpack.tf/profiles/76561198311679551#!/compare/1564790400/1564876800

SALE 5

Sold with an unusual taunt for unknown

https://backpack.tf/profiles/76561198311679551#!/compare/1564876800/1564963200

https://backpack.tf/profiles/76561198043826027#!/compare/1564876800/1564963200

SALE 6

Sold with a key for?

https://backpack.tf/profiles/76561198236774862#!/compare/1560211200/1560556800

https://backpack.tf/profiles/76561198230732648#!/compare/1560470400/1560556800

SALE 7

Sold for 14 keys + 16 refined

https://backpack.tf/profiles/76561198123511024#!/compare/1561680000/1561852800

https://backpack.tf/profiles/76561198119634686#!/compare/1561766400/1561852800

Rounds down to 14 keys

SALE 8

Sold for 17 keys

https://backpack.tf/profiles/76561198119634686#!/compare/1561939200/1562025600

https://backpack.tf/profiles/76561198132450305#!/compare/1562025600/1562112000

B/o was 18 keys

https://bot.tf/stats/listings/4O5QXXWY

SALE 9

Bulk for eldritch motif

https://backpack.tf/profiles/76561198307602421#!/compare/1558569600/1558742400

https://backpack.tf/profiles/76561198277409359#!/compare/1558569600/1558656000

SALE 10 & 11

MARKETPLACE

33 on july 23 (33 / 1.81 = 18.23 rounding to 18 keys)

33 on july 30 (33 / 1.8 = 18.33 rounding to 18 keys)

https://marketplace.tf/items/tf2/30866;5;u62

Sales at 14 and 17. Marketplace sales at 18 and 18. Taking 14-18 keys.