Item 1: https://backpack.tf/item/8833248641

Sale 1:

https://backpack.tf/profiles/76561198140316312#!/compare/1764374400/1764460800

https://backpack.tf/profiles/76561198133991629#!/compare/1764460800/1764547200

400 keys

Sale 2:

https://backpack.tf/profiles/76561198133991629#!/compare/1766102400/1766188800

https://backpack.tf/profiles/76561198859721638#!/compare/1766102400/1766188800

Bulk for the spelled Chiroptera Venenata Bolted Bicorne

Sale 3:

https://backpack.tf/profiles/76561198859721638#!/compare/1768003200/1768089600

https://backpack.tf/profiles/76561198325595749#!/compare/1768003200/1768089600

Looks like 500 keys

Item 2: https://backpack.tf/item/7903070530

Sale 4:

https://backpack.tf/profiles/76561198101062081#!/compare/1770508800/1770768000

https://backpack.tf/profiles/76561199576382232#!/compare/1768694400/1770681600

375 keys

Item 3: https://backpack.tf/item/4508689614

Sale 5:

Mannco.Store, excluding

Sale 6:

https://backpack.tf/profiles/76561198315558870#!/compare/1768694400/1768867200

https://backpack.tf/profiles/76561199073805105#!/compare/1768780800/1768867200

Bulk

MPTF: https://marketplace.tf/items/tf2/30647;5;u99

Item 4: https://backpack.tf/item/4764501130

Sale 7:

Sold for $675 on Feb 11 2026

Keys were $1.87 https://marketplace.tf/items/tf2/5021;6

675/1.87=360.96 ~361 keys

Sale 8:

Sold for $675 on Feb 13 2026

Keys were $1.86

675/1.86=362.9 ~363 keys

Sales:

361, 363, 375, 400, 500

Sellers:

BPTF - https://imgur.com/IwUMcRY 395 keys (5 days), 400 keys (4 listed at between 1 and 5 months)

MPTF - https://marketplace.tf/items/tf2/30647;5;u99 $880 (~468 keys)

STN - https://stntrading.eu/item/tf2/Unusual+Nebula+Phononaut none

SCM - https://steamcommunity.com/market/listings/440/Unusual%20Phononaut?filter=Nebula https://imgur.com/AmP1Lmb 854€ (~428 keys)

500 looks like an outlier given all those sellers at 400 keys. Given the seller at 395 has only been there for 3 days, I'm still keeping 400 in the range. Going with 361-400 keys