Sale 1:

Sold for Nuts n’ Bolts Company Man (15.5) + <1 key in metal/items

http://www.tf2outpost.com/trade/29254913 - B/O of 15

Seller: https://backpack.tf/profiles/76561198145127094#!/compare/1498867200/1498953600

Buyer: https://backpack.tf/profiles/76561198027335148#!/compare/1498953600/1499126400

X = 15 (Capped by B/O)

Sale 2:

Sold for 14 keys in ~2 weeks

http://www.tf2outpost.com/trade/29338910 - B/O of ~14.2

Seller: https://backpack.tf/profiles/76561198002757046#!/compare/1503446400/1503532800

Buyer: https://backpack.tf/profiles/76561198387994013#!/compare/1503446400/1503532800

X = 14

Sale 3:

Sold for 14 keys in ~1 day

No B/Os on their outpost

Seller: https://backpack.tf/profiles/76561198054758757#!/compare/1502064000/1502150400

Buyer: https://backpack.tf/profiles/76561198073417103#!/compare/1502150400/1502236800

X = 14

Sale 4:

Sold for Factory New Current Event Scattergun (~7) + Orbiting Planets Elf Esteem

http://webcache.googleusercontent.com/search?q=cache:NtjY3EoqKoQJ:www.tf2outpost.com/trade/29267239+&cd=1&hl=en&ct=clnk&gl=au – B/O of ~13.7

Seller: https://backpack.tf/profiles/76561198002757046#!/compare/1499990400/1500076800

Buyer: https://backpack.tf/profiles/76561198349780889#!/compare/1499904000/1500076800

Easily caps at the B/O.

X = 14 (Capped by B/O, rounded up)

Sale 5:

Sold for Miami Nights Waxy Wayfinder (13.5)

No outpost

Seller: https://backpack.tf/profiles/76561198349780889#!/compare/1500076800/1500163200

Buyer: https://backpack.tf/profiles/76561198085269574#!/compare/1500076800/1500163200

X = 14

Sale 6:

Quicksold for 13 keys

http://www.tf2outpost.com/trade/29254098 - B/O of 13

Seller: https://backpack.tf/profiles/76561198089273715#!/compare/1498521600/1498953600

Buyer: https://backpack.tf/profiles/76561198145127094#!/compare/1498867200/1498953600

X = 13

Sale 7:

Sold for $26 on Marketplace.tf

https://marketplace.tf/items/47;5;u30

https://backpack.tf/item/1156958536

26/2 = 13

X = 13

Sale 8:

Bulk for Green Energy Fro

Seller: https://backpack.tf/profiles/76561198141862365#!/compare/1502236800/1502323200

Buyer: https://backpack.tf/profiles/76561197993332333#!/compare/1502064000/1502323200

Sale 9:

Bulk for Abduction Universal Translator

Seller: https://backpack.tf/profiles/76561198272649108#!/compare/1499990400/1500854400

Buyer: https://backpack.tf/profiles/76561198125564321#!/compare/1500336000/1500422400

Sale 10:

Sold for Circling Heart Gym Rat

No outpost

Seller: https://backpack.tf/profiles/76561198085269574#!/compare/1500249600/1500336000

Buyer: https://backpack.tf/profiles/76561198150445230#!/compare/1500336000/1500508800

Would be better to use on the Gym Rat.

Sale 11:

Sold for Peace Sign Industrial Festivizer

No outpost

Seller: https://backpack.tf/profiles/76561198150445230#!/compare/1500508800/1500595200

Buyer: https://backpack.tf/profiles/76561198099732491#!/compare/1500422400/1500508800

Probably better to use on the Fetivizer due to lack of B/O

Sellers:

15 keys:

https://i.imgur.com/OMY8ML4.png - 24 days

~15.3 keys:

https://i.imgur.com/eeHn5ok.png (2x) re-lists every ~30 mins

https://backpack.tf/item/603590461 - almost 2 months

https://backpack.tf/item/1368096934 - almost 1 month

Sales at:

13 (2x)

14 (4x)

15

Not going to exclude 14 due to just 1 quicksale, sales are far too common here. Will exclude 13 though.

15 seems high with the bot sellers at 15. Excluding 15.

Going with 14 flat.