All thanks to shufflespy

https://backpack.tf/profiles/76561198448747254#!/compare/1643068800/1643241600 - Bulk

https://backpack.tf/profiles/76561198200696439#!/compare/1643328000/1643414400 - Bulk

https://backpack.tf/profiles/76561198204534945#!/compare/1643673600/1643846400 - 8 Keys + ~6 Keys of Items

https://backpack.tf/profiles/76561199228967650#!/compare/1642032000/1642118400 - ?

https://backpack.tf/profiles/76561198841279602#!/compare/1641945600/1642032000 - ?

https://backpack.tf/profiles/76561198139952775#!/compare/1642032000/1642118400 - Bulk sale

https://backpack.tf/profiles/76561198275430446#!/compare/1643241600/1643328000 - ?

The untraceable sale was the Polar Forecast Elf Care Provider, which will get capped at the buyout of 11 Keys + 33 Refined (rounds down to 11)

https://gladiator.tf/listings/61cfab26ca7c87ce2dba994e - This will be too low

https://gladiator.tf/listings/61e01829a0c3a15f9865ce00 - Previous listing for 14 Keys

https://gladiator.tf/listings/61ce78e1de3533bb385db33d - Previous listing for 12 Keys

https://gladiator.tf/listings/61fef7f32aa069f7cf0c4aad - Current listing for 15 Keys

Sold for 29.99$ on marketplace in Jan 7

https://marketplace.tf/items/tf2/330;5;u67

https://backpack.tf/item/1649093250

29.99$/1.83$=16k

Untrace:

https://backpack.tf/profiles/76561198448747254#!/compare/1640908800/1640995200

https://backpack.tf/profiles/76561198850178158#!/compare/1640908800/1640995200

Taking 14k flat

14 Keys flat would work