Sale 1:

https://backpack.tf/profiles/76561198975635935#!/compare/1578096000/1584921600

https://backpack.tf/profiles/76561198153657886#!/compare/1584662400/1584835200

Bulk

Sale 2:

https://backpack.tf/profiles/76561198337442090#!/compare/1582329600/1583020800

https://backpack.tf/profiles/76561198798841999#!/compare/1582416000/1582502400

Untrace

Sale 3:

https://backpack.tf/profiles/76561198798841999#!/compare/1582934400/1583020800

https://backpack.tf/profiles/76561198337734785#!/compare/1583712000/1583798400

Untrace

Sale 4:

https://backpack.tf/profiles/76561198196712118#!/compare/1577836800/1581552000

https://backpack.tf/profiles/76561198054448372#!/compare/1580256000/1580342400

https://steamcommunity.com/market/listings/440/Unusual%20Helmet%20Without%20a%20Home

SCM

Sold for 19.58 CAD

Keys at 3.44 CAD

Total is 5.69 keys

Sale 5:

https://backpack.tf/profiles/76561198054448372#!/compare/1580860800/1580947200

https://backpack.tf/profiles/76561198134546405#!/compare/1580774400/1580860800

Bulk / untrace

Sale 6:

https://backpack.tf/profiles/76561198134546405#!/compare/1580860800/1580947200

https://backpack.tf/profiles/76561198852030014#!/compare/1579219200/1580860800

https://backpack.tf/profiles/76561198134546405#!/compare/1580860800/1580947200

https://backpack.tf/profiles/76561198017164647#!/compare/1580860800/1580947200

https://backpack.tf/profiles/76561198361891514#!/compare/1580860800/1580947200

Bulk / untrace

Sale 7:

https://backpack.tf/profiles/76561198020673987#!/compare/1583107200/1583280000

https://backpack.tf/profiles/76561198018528305#!/compare/1583107200/1583193600

SCM

Sale 8:

https://backpack.tf/profiles/76561198053245033#!/compare/1581379200/1582416000

https://backpack.tf/profiles/76561198188639765#!/compare/1582329600/1582416000

Untrace

Sale 9:

https://backpack.tf/profiles/76561198188639765#!/compare/1582934400/1583020800

https://backpack.tf/profiles/76561198383339557#!/compare/1582588800/1583107200

Untrace

sale 10:

https://backpack.tf/profiles/76561198383339557#!/compare/1583193600/1583366400

https://backpack.tf/profiles/76561198223429284#!/compare/1583193600/1583280000

Bulk

Sale 11, 12:

https://marketplace.tf/items/tf2/732;5;u58

$13.43 / $1.75 = 7.67 keys <--- https://backpack.tf/item/7956947077

$13.30 / $1.75 = 7.60 keys <----https://backpack.tf/item/2512393033

Total sales @:

5.69, 7.6, 7.67 keys

Buyers up to ~6 keys,

seller for ~2 weeks for ~7.5 keys,

Taking 7.5 flat.