Sale 1:

Sold for 8 keys + ~0.5 keys in items

No outpost

Seller: https://backpack.tf/profiles/76561197979222381#!/compare/1527552000/1528329600

Buyer: https://backpack.tf/profiles/76561198070629603#!/compare/1528070400/1528329600

X = 8.5

Sale 2:

Sold for 8 keys + 3 ref

Seller: https://backpack.tf/profiles/76561198311498888#!/compare/1530403200/1530489600

Buyer: https://backpack.tf/profiles/76561198111386009#!/compare/1501977600/1530576000

X = 8

Sale 3:

Sold for 7 keys + ~0.5 keys in metal

Seller: https://backpack.tf/profiles/76561198048851745#!/compare/1529366400/1529452800

Buyer: https://backpack.tf/profiles/76561198151064563#!/compare/1529452800/1529539200

Keys are traceable in the buyer’s backpack. All keys went to Toad as they bought both unusuals seen there from him, but the ID’s match with 7 of the keys.

Metal histories below.

https://backpack.tf/item/6936669268

https://backpack.tf/item/6936669284

https://backpack.tf/item/6936669292

https://backpack.tf/item/6936669313

https://backpack.tf/item/6936669330

https://backpack.tf/item/6936669347

https://backpack.tf/item/6936669435

https://backpack.tf/item/6936669443

https://backpack.tf/item/6936669449

https://backpack.tf/item/6936669491

https://backpack.tf/item/6936669505

https://backpack.tf/item/6936669516

https://backpack.tf/item/6936669536

https://backpack.tf/item/6936669546

https://backpack.tf/item/6936669561

https://backpack.tf/item/6936669579

https://backpack.tf/item/6936669591

https://backpack.tf/item/6936669606

https://backpack.tf/item/6936669620

X = 7.5

Sale 4:

Sold for 7 keys + 21 ref

Seller: https://backpack.tf/profiles/76561198059021831#!/compare/1530748800/1530835200

Buyer: https://backpack.tf/profiles/76561198281956556#!/compare/1530057600/1530835200

X = 7.5

Sale 5:

Sold for 7 keys + ~0.5 keys in metal/items

Seller: https://backpack.tf/profiles/76561198059021831#!/compare/1531180800/1531267200

Buyer: https://backpack.tf/profiles/76561198069821339#!/compare/1529971200/1531267200

X = 7.5

Sale 6:

Sold to a quickbuyer for 7 keys + 6 ref

Seller: https://backpack.tf/profiles/76561198101657879#!/compare/1530835200/1530921600

Buyer: https://backpack.tf/profiles/76561198059021831#!/compare/1530835200/1530921600

X = 7

Sale 7:

Sold to a bot for 7 keys + 1 scrap?

Buyer: https://backpack.tf/profiles/76561198312265776#!/compare/1531180800/1531267200

https://backpack.tf/item/3510891237 - Seller is untraceable. It’s not the one listed here because it leaves their backpack way before it sells.

Bot.tf confirms, but it is unreliable. https://i.imgur.com/NBRHoBJ.png

X = 7?

Sale 7:

Sold for Energy Orb Field Tested Low Profile SMG + cheap items

Seller: https://backpack.tf/profiles/76561198152860593#!/compare/1530835200/1530921600

Buyer: https://backpack.tf/profiles/76561198101657879#!/compare/1530835200/1530921600

Way too high, excluding.

Sellers:

~7.85 keys:

https://i.imgur.com/5BJZf9q.png

https://backpack.tf/item/624135827

https://backpack.tf/item/1354590527

~7.9 keys:

https://i.imgur.com/wI2NfLA.png

https://backpack.tf/item/1594150635

~8.15 keys:

https://i.imgur.com/RYDNaA8.png

https://backpack.tf/item/3510891237

9 keys:

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

https://backpack.tf/item/1310118941

Sales at:

7

7.5 (3x)

8

8.5

And an untraceable sale at 7.

Several sellers for less than 8. Excluding 8.5.

7 looks like an outlier, excluding.

Going with 7.5-8.

https://backpack.tf/profiles/76561198312265776#!/compare/1532649600/1532736000

https://backpack.tf/profiles/76561198049011747#!/compare/1531612800/1533081600

sold for 7 keys + 13 ref (~7.5)

https://backpack.tf/profiles/76561198118720896#!/compare/1532822400/1532995200

https://backpack.tf/profiles/76561198048851745#!/compare/1532908800/1532995200

sold to a quickbuyer for 7 keys + 6 ref (~7)

https://backpack.tf/profiles/76561198112336424#!/compare/1532563200/1532649600

https://backpack.tf/profiles/76561198104512843#!/compare/1532563200/1532649600

sold for 7 keys + 28 ref (~8)

total of 2 sales at 8, 2 sales at 7, and 4 sales at 7.5.

Not including 7, as it still doesn't seem too common.