Study

Item 1

https://backpack.tf/item/8064994614

Sale 1

Bought off MP, sale pre-whitelist

Item 2

https://backpack.tf/item/6440010549

Sale 2

https://backpack.tf/profiles/76561198061489334#!/compare/1610496000/1610755200

https://backpack.tf/profiles/76561198071346629#!/compare/1610668800/1610755200

Sold for 20 keys

https://gladiator.tf/listings/600206712b775ee628aa253c - buyout 20 keys

Sale 3

Dumped to tradeit

Item 3

https://backpack.tf/item/6090301693

Sale 4

Delisted off MP

Sale 5

https://backpack.tf/profiles/76561198154700747#!/compare/1608076800/1608163200

https://backpack.tf/profiles/76561199025158544#!/compare/1607990400/1608076800

Sold to tftrade.ru

Sale 6

https://backpack.tf/profiles/76561199025158544#!/compare/1608854400/1608940800

https://backpack.tf/profiles/76561198886850124#!/compare/1608854400/1608940800

Untrace

Sale 7

https://backpack.tf/profiles/76561198886850124#!/compare/1608940800/1609027200

https://backpack.tf/profiles/76561198841279602#!/compare/1608854400/1608940800

Untrace

Sale 8

https://backpack.tf/profiles/76561198841279602#!/compare/1609718400/1609804800

https://prnt.sc/xtekc6 - 14 keys match, history here - https://backpack.tf/item/8904073056

Erik purchase - https://gladiator.tf/listings/5ff49871da5c741b78a2afbd - buyout 14 keys

Taking 14 keys here

Item 4

https://backpack.tf/item/5974140100

Sale 9

https://backpack.tf/profiles/76561198079422043#!/compare/1609372800/1609804800

https://backpack.tf/profiles/76561198032541527#!/compare/1609459200/1609632000

Untrace

Sale 10

https://backpack.tf/profiles/76561198032541527#!/compare/1609632000/1609718400

https://backpack.tf/profiles/76561198123789684#!/compare/1609545600/1609632000

2 keys match

Sale 11

https://backpack.tf/profiles/76561198123789684#!/compare/1609632000/1609891200

https://backpack.tf/profiles/76561198993631639#!/compare/1609545600/1609632000

Untrace

Sale 12

https://backpack.tf/profiles/76561198993631639#!/compare/1609977600/1610064000

https://backpack.tf/profiles/76561198349986297#!/compare/1609977600/1610064000

Untrace

Item 5

https://backpack.tf/item/5798349261

Sale 13

https://backpack.tf/profiles/76561199038727876#!/compare/1607212800/1607299200

https://backpack.tf/profiles/76561198072484882#!/compare/1590105600/1607299200

Untrace

Sale 14

https://backpack.tf/profiles/76561198072484882#!/compare/1590105600/1607299200

https://backpack.tf/profiles/76561198986747837#!/compare/1607212800/1607299200

Untrace

Sale 15

https://backpack.tf/profiles/76561198986747837#!/compare/1607299200/1607385600

https://backpack.tf/profiles/76561198037674114#!/compare/1606867200/1607385600

Untrace

Sale 16

https://backpack.tf/profiles/76561198037674114#!/compare/1610323200/1610582400

https://backpack.tf/profiles/76561198850274253#!/compare/1610496000/1610582400

Untrace

Sale 17

https://backpack.tf/profiles/76561198850274253#!/compare/1610755200/1610841600

https://backpack.tf/profiles/76561198993873071#!/compare/1610755200/1610928000

Sold for 15 keys

https://gladiator.tf/listings/600484ccb6ca4f1a1958885b - 13 keys buyout

Taking 13 keys, assuming other stuff also got bought too

Marketplace sales

https://marketplace.tf/items/tf2/30866;5;u19

Dec 10th - $33.99 / $1.81 = 18.78 keys

Hidden history

https://backpack.tf/item/9711547416

Sale 1

https://backpack.tf/profiles/76561198044800742#!/compare/1611360000/1611446400

https://backpack.tf/profiles/76561198091502579#!/compare/1611273600/1611360000

Untrace

Sales

20, 14, 13, 19

Current Listings

https://prnt.sc/xteyc0

4 month unsold at 17 keys, not sure how 20 keys sold at the same time 17 keys was listed

Uhhh, I guess ranging 13 - 19 keys here to be fair

Thanks Blaze:

https://backpack.tf/profiles/76561198906444941#!/compare/1613001600/1614729600

https://backpack.tf/profiles/76561198337734785#!/compare/1613433600/1614470400

https://gladiator.tf/sales?item=Circling%20Heart%20Warhood - sold for 15~ keys

there are 3 sellers now at 17 (one of which is now 5 months old) and buyers are up to 14 atm. the range seems a bit too large atm, maybe 14 - 15 would work here instead

Taking 14 – 15 keys