Item 1: https://backpack.tf/item/16447051624

Sale 1: Bot dump

https://backpack.tf/profiles/76561198139677993#!/compare/1766188800/1766448000

https://backpack.tf/profiles/76561199072654974#!/compare/1766361600/1766448000

Sale 2: 25k 19.44r > 25k (19.44/54.325 ref to key = .36k) > 25.36k

https://backpack.tf/profiles/76561199072654974#!/compare/1770076800/1770163200

https://backpack.tf/profiles/76561198128280119#!/compare/1770163200/1770249600

Item 2: https://backpack.tf/item/15495396943

Sale 1: Bulk

https://backpack.tf/profiles/76561198125791160#!/compare/1770595200/1770681600

https://backpack.tf/profiles/76561198073153164#!/compare/1769817600/1770681600

Item 3: https://backpack.tf/item/13618567932

Sale 1: Untrace

https://backpack.tf/profiles/76561199177132803#!/compare/1769731200/1769817600

https://backpack.tf/profiles/76561199657747540#!/compare/1769817600/1769904000

Sale 2: Bot dump

https://backpack.tf/profiles/76561199657747540#!/compare/1770422400/1770508800

https://backpack.tf/profiles/76561199059698603#!/compare/1770422400/1770508800

Sale 3: Bought, traded back to Quicksell.store same day

https://backpack.tf/profiles/76561199059698603#!/compare/1771372800/1771459200

https://backpack.tf/profiles/76561199087135121#!/compare/1771372800/1771459200

Sale 4: Bot dump

https://backpack.tf/profiles/76561199087135121#!/compare/1771372800/1771459200

https://backpack.tf/profiles/76561199110809353#!/compare/1771372800/1771459200

Item 4: https://backpack.tf/item/10837341421

Sale 1: Bot dump / private inventory making untrace

https://backpack.tf/profiles/76561198096823209#!/compare/1771804800/1771891200

https://backpack.tf/profiles/76561198349848918#!/compare/1771804800/1771891200

Item 5: https://marketplace.tf/items/tf2/31212;5;u199

Sale 1: Marketplace sale, listed below.

Sale 2: Untrace

https://backpack.tf/profiles/76561198257385833#!/compare/1768003200/1769212800

https://backpack.tf/profiles/76561199572351680#!/compare/1769040000/1769212800

Item 6: https://backpack.tf/item/10744625637

Sale 1: 27k 27.88r > 27k (27.88/57.89 ref to key (at time of sale) = .48k) > 27.48k

https://backpack.tf/profiles/76561198349848918#!/compare/1771286400/1771372800

https://backpack.tf/profiles/76561198947812176#!/compare/1771286400/1771372800

Marketplace sale:

https://marketplace.tf/items/tf2/31212;5;u199

Sold for $59.99 on Jan 6th

https://marketplace.tf/items/tf2/5021;6

Key price for the day is $1.85

$59.99 / $1.85 = 32.43k

Sales at 25.36k, 27.51k, and 32.43k. 32.43k excluded as massive outlier above unsolds, 27.48k can also squeeze in here, even though it's above unsolds at 26k, the higher end supports taking this (as does the recency of listings). Additionally, with how small the margins are here, it seems like 25-27k is a common enough trading point that it fits as well. Taking 25.36k rounded down to 25k for the low end, and 27.48k rounded down to 27k for the high end.