I can do this too.

Sale #1:

$60 marketplace.tf ~32 keys @ $1.9 per key (Jan 22)

https://marketplace.tf/items/30845;5;u3005

Sale #2:

Sold with Mallard Modest for Vivid Cotton (unusable)

https://backpack.tf/profiles/76561198074747394#!/compare/1513468800/1513641600

https://backpack.tf/profiles/76561198021055079#!/compare/1513555200/1513641600

Sale #3:

Not sure

https://backpack.tf/profiles/76561198305578110#!/compare/1517011200/1517184000

Sale #4:

Vivid Mullet (17*) + ~4 keys in items = 21 keys

https://backpack.tf/profiles/76561198358646453#!/compare/1516320000/1516406400

https://backpack.tf/profiles/76561198215211781#!/compare/1516320000/1516406400

Sale #5:

Sold for Max's Head = 19.6, rounds to 20 keys

https://backpack.tf/profiles/76561198215211781#!/compare/1515110400/1515715200

https://backpack.tf/profiles/76561198168625615#!/compare/1515628800/1515715200

Sale #6:

Sold for Amaranthine Bombing Run (39) + ~0.5 keys in items = 39.5, rounds to 40 keys

https://backpack.tf/profiles/76561197991710942#!/compare/1514592000/1514678400

https://backpack.tf/profiles/76561198168625615#!/compare/1514678400/1514764800

Kinda outlier-ish given the sellers and the difference in value from the sales around 20

Sale #7:

SCM maybe

https://backpack.tf/profiles/76561198326553115#!/compare/1515542400/1516060800

Sale #8:

Miami Fed-Fightin' Fedora (outdated at 28, has a buyer at 22 at time of posting)

https://backpack.tf/profiles/76561198165983641#!/compare/1515542400/1515628800

https://backpack.tf/profiles/76561198138064828#!/compare/1515628800/1515715200

Supports range

Sale #9:

Appears to have sold with 8 keys for Miami Pot (22.5) = 14.5, rounds to 15 keys

https://backpack.tf/profiles/76561198040919417#!/compare/1515283200/1515369600

https://backpack.tf/profiles/76561198093765664#!/compare/1515283200/1515369600

Would be a bit low

Sale #10:

Appears to be 20 pure but a bit hard to say

https://backpack.tf/profiles/76561198149459336#!/compare/1515542400/1515628800

https://backpack.tf/profiles/76561198040919417#!/compare/1515283200/1515369600

Sale #11:

Sold with ~5 keys in stuff for Cool FN Blitzkrieg SMG (2 years outdated at 25)

https://backpack.tf/profiles/76561198141456468#!/compare/1515456000/1515542400

https://backpack.tf/profiles/76561198361642456#!/compare/1515456000/1515542400

Not gonna mini that SMG but should fit close into range

Sale #12:

Blizz B'aaarrgh-n-Bicorne + Whirlwind Mannrobics

https://backpack.tf/profiles/76561197994619898#!/compare/1514419200/1514505600

Both would need minis but this may be pretty high

Vivid Mullet:

Sold for Miami Connoisseur's (14.5) + 1 key + ~1.5 key item = 17 keys

https://backpack.tf/profiles/76561197996095002#!/compare/1516147200/1516233600

Sellers:

https://i.imgur.com/tRMszM0.png

https://backpack.tf/item/6362900459 24

https://backpack.tf/item/6260661142 24

https://backpack.tf/item/6260531294 25

https://backpack.tf/item/6398757413 40

https://backpack.tf/item/6256499398 45

Using the sales at 20-32 to make the range. The lowest (14) and highest (40) sales are excluded. Current sellers fall within this range. I don't want to leave out 32 when it's a pure sale just because there are sellers asking less, especially when there are higher sales. A wider range would seem appropriate here.

welp proof no longer looks valid and things seemed to have dropped off.

Because it's been a month and this is a taunt.