There are more indate transactions to consider and analyse:

OK,Scanned page 1

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Found 4 instances with non-empty history.

[Instance #0]: https://backpack.tf/item/11880252551

[Transaction #0]:

https://backpack.tf/profiles/76561198063678048#!/compare/1416297600/1662249600

https://backpack.tf/profiles/76561199132627345#!/compare/1661126400/1661644800

Checking for common item ids on both sides of transaction:

[Added]:

Kill-a-Watt Heer's Helmet - 18.524 keys - 1 items

[Removed]:

[Sum added]: 18.524 keys

[Sum removed]: 0 keys

[Transaction #1]:

https://backpack.tf/profiles/76561199132627345#!/compare/1659484800/1659830400

https://backpack.tf/profiles/76561198123166689#!/compare/1659830400/1660089600

Checking for common item ids on both sides of transaction:

[Added]:

Kill-a-Watt Heer's Helmet - 18.524 keys - 1 items

[Removed]:

[Sum added]: 18.524 keys

[Sum removed]: 0 keys

[Instance #1]: https://backpack.tf/item/7958653039

[Transaction #0]:

https://backpack.tf/profiles/76561198834125540#!/compare/1667174400/1667260800

https://backpack.tf/profiles/76561199199136084#!/compare/1667174400/1667260800

Checking for common item ids on both sides of transaction:

[Added]:

Arcane Assistance Taunt: Scotsmann's Stagger - 29.538 keys - 1 items

Aurora Australis Taunt: Scotsmann's Stagger - 0.0 keys - 1 items

Aurora Polaris Taunt: The Boston Boarder - 0.0 keys - 1 items

Cavalier de Carte Taunt: Mannrobics - 0.0 keys - 1 items

Circling TF Logo Elf Esteem - 9.762 keys - 1 items

Cloud 9 Archer's Sterling - 11.014 keys - 1 items

Cloud 9 Bolted Birdcage - 11.014 keys - 1 items

Emerald Allurement Taunt: The Box Trot - 7.76 keys - 1 items

Fountain of Delight Taunt: Soldier's Requiem - 4.255 keys - 1 items

Frightened Poltergeist Hat Outta Hell - 0.0 keys - 1 items

Galvanic Defiance Taunt: Luxury Lounge - 0.0 keys - 1 items

Kill-a-Watt Heer's Helmet - 18.524 keys - 1 items

Max's Severed Head - 28.186 keys - 1 items

Miami Nights Deep Cover Operator - 20.026 keys - 1 items

Miami Nights Noble Amassment of Hats - 23.53 keys - 1 items

Minty Cypress Taunt: Kazotsky Kick - 0.0 keys - 1 items

Mirthful Mistletoe Jolly Jingler - 9.762 keys - 1 items

Searing Plasma Galvanized Gibus - 34.544 keys - 1 items

Shimmering Lights Taunt: Bad Pipes - 6.258 keys - 1 items

Starstorm Slumber Nasty Norsemann - 18.524 keys - 1 items

Static Mist Taunt: Surgeon's Squeezebox - 12.516 keys - 1 items

Strange Kill-a-Watt Big Chief - 7.76 keys - 1 items

Thundering Spirit Taunt: Mannrobics - 0.0 keys - 1 items

Wispy Halos Taunt: Scotsmann's Stagger - 0.0 keys - 1 items

[Removed]:

[Sum added]: 252.973 keys

[Sum removed]: 0 keys

[Transaction #1]:

no proper comparison found

https://backpack.tf/profiles/76561198263236870#!/compare/1662508800/1663027200

[Instance #2]: https://backpack.tf/item/7957354543

[Transaction #0]:

https://backpack.tf/profiles/76561199084784906#!/compare/1666742400/1666828800

https://backpack.tf/profiles/76561198311498888#!/compare/1666742400/1666915200

Checking for common item ids on both sides of transaction:

[Added]:

Kill-a-Watt Heer's Helmet - 18.524 keys - 1 items

[Removed]:

[Sum added]: 18.524 keys

[Sum removed]: 0 keys

[Instance #3]: https://backpack.tf/item/7461459599