Credit to Lemons for the help!

Sale 1) 998 Keys

https://backpack.tf/item/2049877793

https://backpack.tf/profiles/76561198057452720#!/compare/1714435200/1714694400

https://backpack.tf/profiles/76561198118701901#!/compare/1714435200/1714694400

Round to 1000 Keys for neatness.

Sale 2) 1200 Keys

https://backpack.tf/item/2049877793

https://backpack.tf/profiles/76561198118701901#!/compare/1718323200/1718496000

https://backpack.tf/profiles/76561198063640894#!/compare/1718323200/1718496000

Sale 3)

https://backpack.tf/item/2049877793

https://backpack.tf/profiles/76561198033378852#!/compare/1718755200/1718841600

https://backpack.tf/profiles/76561198063640894#!/compare/1718755200/1718841600

https://imgur.com/a/Fl6X7mb

Sold for Vicious Circle Lucky Cat Hat(Outdated Suggestion at 709 Keys), Pumpkin Party Cat Pajamas (Recently priced at 285 keys - https://backpack.tf/stats/Unusual/Cat's%20Pajamas/Tradable/Craftable/163), Circling Heart Stormin Norman, Blizzardy Storm Headgear Honcho, and Ominous Stare Elf Esteem

Lemons: 

Looking at the Vicious Circle Lucky Cat Hat

Only sale:

https://backpack.tf/profiles/76561198271915998#!/compare/1720828800/1720915200

https://backpack.tf/profiles/76561198063640894#!/compare/1720828800/1720915200 - Sold for a Morning Glory Grimm Hatte (308) + a Burning Flames Sole Mate (72) + a Disco Beat Down Front Runner (65) + a It's A Secret To Everybody Prince Tavish's Crown (540) = 985 keys

The Grimme Hatte needs to be redone - https://backpack.tf/suggestion/6654dc8b59200b2da0024c8f - but if we take 306-310 as a rough mini it proves the Cat Hat is more than 709 keys.

+ Pumpkin Party Cat's Pajamas (285) + Circling Heart Stormin' Norman (27, using buyers) + Blizzardy Storm Honcho's Headgear (30, using buyers)

= 985 + 285 + 27 + 30 = 1327.

This would round to 1350 (to the nearest 50) which accounts for the Honcho and Norman being low.

1000-1350 is fine.