https://backpack.tf/profiles/76561198002186909#!/compare/1501545600/1501632000

https://backpack.tf/profiles/76561198131986842#!/compare/1501545600/1501632000

Prof KS SMG (9) + Infernal Battin' (sugg @15) = 24 keys

No b/o

https://backpack.tf/profiles/76561198002186909#!/compare/1501027200/1501113600

Bulk

https://backpack.tf/profiles/76561198150334241#!/compare/1500768000/1500940800

https://backpack.tf/profiles/76561198195731583#!/compare/1500854400/1500940800

Blizz Humanball (23.5) = 24

No b/o

https://backpack.tf/profiles/76561198131986842#!/compare/1501632000/1502064000

https://backpack.tf/profiles/76561198195731583#!/compare/1501977600/1502064000

With 11 keys for Nethertail Sombrero = low

https://backpack.tf/profiles/76561198075108450#!/compare/1503273600/1503360000

Sold in 3 days for 18 pure, qs

https://backpack.tf/profiles/76561198255422669#!/compare/1503273600/1503360000

T-w Blast Defence (23)

http://www.tf2outpost.com/trade/29338693 - b/o of 19

It's sold in 1 day so fair to skip the b/o here and take 23

https://backpack.tf/profiles/76561198255422669#!/compare/1505088000/1505260800

Max's (18) + <0.5 key = 18

https://backpack.tf/profiles/76561198043978630#!/compare/1505260800/1505347200

16 pure, qs - sold in 3 days

https://backpack.tf/profiles/76561198139732126#!/compare/1505606400/1505692800

Bulk

https://backpack.tf/profiles/76561198122471148#!/compare/1505606400/1505952000

http://www.tf2outpost.com/trade/29372174 - caps @24 b/o

Summary

Seems like we have 3 sales @24, sale @23 and one @18

18 looks like an outliner

23-24 range