Item 1: https://backpack.tf/item/16618235712

Sale 1:

Mannco.Store, excluding

Item 2: https://backpack.tf/item/16465785176

Sale 2:

https://backpack.tf/profiles/76561198385366296#!/compare/1764806400/1765065600

https://backpack.tf/profiles/76561199004803157#!/compare/1765065600/1765152000

Untrace

Sale 3:

https://backpack.tf/profiles/76561199004803157#!/compare/1766361600/1766275200

https://backpack.tf/profiles/76561198380634252#!/compare/1766361600/1766275200

Untrace

Sale 4:

https://backpack.tf/profiles/76561198380634252#!/compare/1766275200/1766361600

https://backpack.tf/profiles/76561199111292616#!/compare/1766275200/1766361600

Untrace

Item 3: https://backpack.tf/item/15914932864

Sale 5:

https://backpack.tf/profiles/76561198062747535#!/compare/1769644800/1769731200

https://backpack.tf/profiles/76561198223779024#!/compare/1766793600/1769731200

Looks like 44 keys

Item 4: https://backpack.tf/item/14802054125

Quicksell.Store bot transfer

Item 5: https://backpack.tf/item/14264403359

Sale 6:

https://backpack.tf/profiles/76561198264786606#!/compare/1765670400/1766188800

https://backpack.tf/profiles/76561199875222078#!/compare/1766188800/1766275200

Bulk

Sale 7:

https://backpack.tf/profiles/76561199875222078#!/compare/1766188800/1766275200

https://backpack.tf/profiles/76561199111292616#!/compare/1766102400/1766188800

Bulk

Sale 8:

https://backpack.tf/profiles/76561199111292616#!/compare/1766275200/1766361600

https://backpack.tf/profiles/76561199183171982#!/compare/1766275200/1766361600

Looks like an account transfer, then listed on MPTF

Item 6: https://backpack.tf/item/8215120347

Sale 9:

https://backpack.tf/profiles/76561198349848918#!/compare/1764806400/1764892800

https://backpack.tf/profiles/76561198805070153#!/compare/1764547200/1764892800

Untrace

Sale 10:

https://backpack.tf/profiles/76561198805070153#!/compare/1764979200/1765152000

https://backpack.tf/profiles/76561199072652703#!/compare/1764892800/1764979200

Bot dump, untrace

Sale 11:

https://backpack.tf/profiles/76561199072652703#!/compare/1764979200/1765065600

https://backpack.tf/profiles/76561198088878793#!/compare/1764979200/1765065600

31 keys match in seller's compare but I see 36 keys and 63 ref in the buyer's compare, taking 37 keys

Sale 12:

https://backpack.tf/profiles/76561198088878793#!/compare/1771286400/1771372800

https://backpack.tf/profiles/76561198135386781#!/compare/1771200000/1771372800

Only 1 key matches

Sale 13:

https://backpack.tf/profiles/76561198135386781#!/compare/1771632000/1771718400

https://backpack.tf/profiles/76561198050726553#!/compare/1771632000/1771718400

Bulk for the Spelled Strange Pro KS Original

Sale 14:

https://backpack.tf/profiles/76561198050726553#!/compare/1771718400/1772064000

https://backpack.tf/profiles/76561198267425271#!/compare/1771718400/1771977600

46 keys

Item 7: https://backpack.tf/item/7957451721

Sale 15:

https://backpack.tf/profiles/76561199092398021#!/compare/1770940800/1772668800

https://backpack.tf/profiles/76561199420273036#!/compare/1770681600/1771459200

Untrace

Sale 16:

https://backpack.tf/profiles/76561199420273036#!/compare/1771459200/1772064000

https://backpack.tf/profiles/76561199026390261#!/compare/1771977600/1772064000

Dumped to STN for 44 keys and 40.11 ref, rounds to 45

Item 8: https://backpack.tf/item/2177946495

Sale 17:

https://backpack.tf/profiles/76561197966705755#!/compare/1768867200/1769299200

https://backpack.tf/profiles/76561198109719754#!/compare/1765065600/1770163200

Bulk

Sale 18:

https://backpack.tf/profiles/76561198109719754#!/compare/1770249600/1770422400

https://backpack.tf/profiles/76561197966705755#!/compare/1769299200/1770508800

Bulk/tradeback

MPTF: https://marketplace.tf/items/tf2/538;5;u56

Item 9: https://backpack.tf/item/10433474734

Sale 19:

Sold for $95 on Feb 27 2026

Keys were $1.88 https://marketplace.tf/items/tf2/5021;6

95/1.88=50.53 ~51 keys

Sales:

37, 44, 45, 46, 51

Sellers:

BPTF - https://imgur.com/z6XSFIv ~49 keys (appears to be 1 minute but QSStore has owned it since late December

MPTF - https://marketplace.tf/items/tf2/538;5;u56 $95 (~50 keys)

STN - https://stntrading.eu/item/tf2/Unusual+Kill-a-Watt+Killer+Exclusive 48 keys 7.88 ref, buy order at 44 keys (inactive since they already have one)

SCM - https://steamcommunity.com/market/listings/440/Unusual%20Killer%20Exclusive?filter=Kill-a-Watt https://imgur.com/BDV0SQD 84.56€ (~42 keys)

I would call 37 low given 45 was a buy order dump and the fact that it sold within a day, however if I do that the whole range will be above a seller. It's 1 key above buyers so should be fine to use as the low end. 51 however seems a bit on the high side with the lower sellers.

Going with 37-46 keys