Item 1

https://backpack.tf/item/8172841929

Sale #1

Only a few keys and metal match with ID "13495155154" of the unusual, incomplete and untraceable-

Seller: https://backpack.tf/profiles/76561198321576432#!/compare/1694044800/1694217600

Buyer: https://backpack.tf/profiles/76561199108309959#!/compare/1693958400/1694044800

Sale #2

Bulk transfer?-

Seller: https://backpack.tf/profiles/76561199108309959#!/compare/1694044800/1694131200

Buyer: https://backpack.tf/profiles/76561198086011812#!/compare/1693872000/1694131200

Item 2

https://backpack.tf/item/8160468812

Trade back happened at the beginning of the history so not using those sales

Sale #3

Sold for 17 keys (keys in the buyer's side match)-

Seller: https://backpack.tf/profiles/76561198120538194#!/compare/1696032000/1696118400

Buyer: https://backpack.tf/profiles/76561198319932595#!/compare/1696032000/1696118400

Marketplace.tf Sales

https://marketplace.tf/items/tf2/31058;5;u131

MP.TF Sale #1-2

Sold for $38.39 on August 1, 2023

Average Key Price @ $1.95ish

38.39/1.95 = 19.68ish keys

Unknown Histories

MP.TF Sale #3

Sold for $35.92 on September 24, 2023

Average Key Price @ $2.02ish

35.92/2.02 = 17.78ish keys

Unknown History

MP.TF Sale #4

Sold for $35.92 on September 30, 2023

Average Key Price @ $2.03ish

35.92/2.03 = 17.69ish keys

Unknown History

MP.TF Sale #5

Sold for $35.92 on October 11, 2023

Average Key Price @ $2.04ish

35.92/2.04 = 17.60ish keys

https://backpack.tf/item/8172841929

Sales @ 17, 18, 18, 18, 20, 20

Taking 17-18 here