Item 1: https://backpack.tf/item/16418358795

Sale 1: Bulk

https://backpack.tf/profiles/76561198075086238#!/compare/1766016000/1766102400

https://backpack.tf/profiles/76561198078864424#!/compare/1765584000/1766102400

Sale 2: Bot dump for 12k 5r

https://backpack.tf/profiles/76561199186541168#!/compare/1766275200/1766361600

https://backpack.tf/profiles/76561198078864424#!/compare/1766102400/1766361600

Item 2: https://backpack.tf/item/12202638659

Sale 1: Untrace, not seen entering buyer's BP, keys don't match

https://backpack.tf/profiles/76561198221078288#!/compare/1761696000/1761782400

https://backpack.tf/profiles/76561198012503085#!/compare/1761696000/1761782400

Sale 2: Untrace, not seen exiting seller's BP, no incoming keys from buyer

https://backpack.tf/profiles/76561198349848918#!/compare/1761696000/1761782400

https://backpack.tf/profiles/76561198012503085#!/compare/1761782400/1761868800

Sale 3: 17k, 15r (ID: 16541548700)

https://backpack.tf/profiles/76561198349848918#!/compare/1766275200/1766361600

https://backpack.tf/profiles/76561198013121180#!/compare/1765929600/1766361600

Matching key: https://backpack.tf/item/15954005801

Sale 4: Bulk

https://backpack.tf/profiles/76561199802101302#!/compare/1767657600/1767744000

https://backpack.tf/profiles/76561198013121180#!/compare/1767657600/1767744000

Item 3: https://backpack.tf/item/12199020904

Sale 1: Marketplace sale (Presumably the Dec. 11th one, based on dates)

Presumably dumped to an STN bot after this, but due to the massive date mismatch, impossible to tell when this occurred or the nature of the movement, since the person seems to have nothing in their inventory when I checked.

Marketplace sales:

https://marketplace.tf/items/tf2/31310;5;u261

Sold for $45 on Dec 11th and Dec 31st

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

Key prices are $1.80 for Dec. 11th and $1.85 for Dec 31st

Dec. 11th: $45 / $1.80 = 25k

Dec. 31st: $45 / $1.85 = 24.32k

Classifieds link: https://imgur.com/a/eOwsv9M

Sales at 17k 15r, 24.32k, and 25k. Two unsolds for one month each at 23k excludes the two marketplace sales, leaving us with the 17k 15r sale for the single value. Rounding off the ref and taking 17k for the sole value.