Using last month.

Sale 1:

Sold for 4 keys + 26 ref?

Seller: https://backpack.tf/profiles/76561198312583107#!/compare/1534636800/1534723200

Buyer: https://backpack.tf/profiles/76561198301755987#!/compare/1534636800/1534723200

https://backpack.tf/item/6758797672

https://i.imgur.com/kUruJ5Z.png

All the keys and most of the ref matches, should be fine to assume that bot.tf is correct. If not, it should still fall into the range.

X = 5

Sale 2:

Sold for 5 keys

Seller: https://backpack.tf/profiles/76561198335791307#!/compare/1535846400/1535932800

Buyer: https://backpack.tf/profiles/76561198129334953#!/compare/1535760000/1535932800

https://backpack.tf/item/5622113256

https://i.imgur.com/kUruJ5Z.png

X = 5

Sale 3:

Sold for 5 keys

Seller: https://backpack.tf/profiles/76561198335791307#!/compare/1536451200/1536537600

Buyer: https://backpack.tf/profiles/76561198107223339#!/compare/1535155200/1536537600

https://backpack.tf/item/5622113256

X = 5

Sale 4:

Sold with a small amount of ref for 5 keys

Seller: https://backpack.tf/profiles/76561198305676157#!/compare/1535760000/1535846400

Buyer: https://backpack.tf/profiles/76561198144191935#!/compare/1535587200/1535846400

https://backpack.tf/item/2698602010

X = 5

Sale 5:

Sold for 5 keys

Seller: https://backpack.tf/profiles/76561198335791307#!/compare/1534809600/1534896000

Buyer: https://backpack.tf/profiles/76561198446620558#!/compare/1534636800/1534896000

https://backpack.tf/item/5622113256

https://i.imgur.com/kUruJ5Z.png

X = 5

Sale 6:

Sold for 4 keys + ~0.5 keys in items

Seller: https://backpack.tf/profiles/76561198312583107#!/compare/1536530400/1536616800

Buyer: https://backpack.tf/profiles/76561198102362159#!/compare/1536537600/1537228800

https://backpack.tf/item/6766477070

https://i.imgur.com/kUruJ5Z.png

X = 4.5

Sale 7:

Sold to a bot for 4 keys

Seller: https://backpack.tf/profiles/76561198317608743#!/compare/1536883200/1536969600

Buyer: https://backpack.tf/profiles/76561198335791307#!/compare/1536883200/1536969600

https://backpack.tf/item/2980479696

https://i.imgur.com/kUruJ5Z.png - labelled as 4 keys and 5 ref, wouldn’t affect the price if ref actually was involved.

X = 4

Sale 8:

Sold for $5.45 on marketplace.tf

https://marketplace.tf/items/1119;5;u3001

Can’t find the history.

This will be significantly lower than classified’s quickbuyers. Excluding.

Other Sales:

https://backpack.tf/item/6550840092 (#1-3)

https://backpack.tf/item/6253314246 (#4)

https://backpack.tf/item/5622113256 (#5 & #6)

https://backpack.tf/item/4761664129 (#7)

https://backpack.tf/item/3635346608 - mannco.trade/gambled

https://backpack.tf/item/4593231495 - tf2mart/scm

https://backpack.tf/item/6703349179 - mannco.trade stuff

https://backpack.tf/item/6636033052 - tf2mart stuff

https://backpack.tf/item/6261246424 - Gambled/mannco.trade/tradeit

https://backpack.tf/item/2704438226 - Gambled

#1

SCM

https://backpack.tf/profiles/76561198087268284#!/compare/1535587200/1535673600

https://backpack.tf/profiles/76561198079098551#!/compare/1535587200/1535760000

#2

Bulk for Pro. KS Aus Scattergun

https://backpack.tf/profiles/76561198079098551#!/compare/1537142400/1537228800

https://backpack.tf/profiles/76561198416865066#!/compare/1537142400/1537228800

#3

Bulk for Orbiting Fire Tipped Lid

https://backpack.tf/profiles/76561198416865066#!/compare/1537142400/1537228800

https://backpack.tf/profiles/76561198285721949#!/compare/1537142400/1537228800

#4

Untraceable

https://backpack.tf/profiles/76561198313362742#!/compare/1534723200/1535760000

https://backpack.tf/profiles/76561198169153665#!/compare/1534723200/1536796800

#5

Same links from sale 5, but traded back the day it was bought

https://backpack.tf/profiles/76561198446620558#!/compare/1534636800/1534896000

https://backpack.tf/profiles/76561198335791307#!/compare/1534809600/1534896000

https://i.imgur.com/kUruJ5Z.png - labelled as 4 keys + 5 ref

#6

Untraceable

https://backpack.tf/profiles/76561198129334953#!/compare/1535932800/1536105600

https://backpack.tf/profiles/76561198335791307#!/compare/1536019200/1536105600

https://i.imgur.com/kUruJ5Z.png - labelled as 4 keys + 5 ref

#7

Untraceable

https://backpack.tf/profiles/76561198168186159#!/compare/1536192000/1537228800

https://backpack.tf/profiles/76561198311498888#!/compare/1537142400/1537228800

Currently, 1 key and 21 ref match, but that’s subject to change as the compare link may become skewed by the seller buying stuff with the pure.

Sellers:

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

https://backpack.tf/item/2980479696 - 5 keys

Sales at:

4

4.5

5 (5x)

Going with 4-5.