Using last month

Sale 1:

Sold for Steaming Trucker's Topper (Mini at 13.5 below)

http://www.tf2outpost.com/trade/29598178 - B/O of 12

Seller: https://backpack.tf/profiles/76561198202694983#!/compare/1522886400/1523059200

Buyer: https://backpack.tf/profiles/76561198152434713#!/compare/1522627200/1523059200

X = 12

Sale 2:

Sold for 11 keys

Seller: https://backpack.tf/profiles/76561198386348408#!/compare/1521763200/1521849600

Buyer: https://backpack.tf/profiles/76561198029648847#!/compare/1521504000/1522195200

X = 11

Sale 3:

Sold for 10 keys

Seller: https://backpack.tf/profiles/76561198048851745#!/compare/1521590400/1521676800

Buyer: https://backpack.tf/profiles/76561198061455028#!/compare/1521504000/1522540800

X = 10

Sale 4:

Quicksold for 9 keys

Seller: https://backpack.tf/profiles/76561198406770202#!/compare/1523059200/1523145600

Buyer: https://backpack.tf/profiles/76561198039844252#!/compare/1522886400/1523059200

X = 9

Sale 5:

Sold for either a Smoking Gym Rat or 8 keys

Seller: https://backpack.tf/profiles/76561198074161948#!/compare/1522540800/1523145600

Buyer: https://backpack.tf/profiles/76561198406770202#!/compare/1522972800/1523059200

Either way, it's lower than quickbuyer price.

Sale 6:

Bulk for Australium Rocket Launcher

Seller: https://backpack.tf/profiles/76561198117428039#!/compare/1523318400/1523404800

Buyer: https://backpack.tf/profiles/76561198026194410#!/compare/1523232000/1523318400

Steaming Trucker's Topper Mini:

Sale 1:

Sold for Steaming Hot Dogger (Suggestion at 16)

http://www.tf2outpost.com/trade/29612445 - B/O of 15, seller confirms sale

Seller: https://backpack.tf/profiles/76561198202694983#!/compare/1522886400/1523059200

Buyer: https://backpack.tf/profiles/76561198116724032#!/compare/1522972800/1523059200

X = 15 (Capped by B/O)

Sale 2:

Sold for Kill-a-Watt Trencher's Topper

No outpost

Seller: https://backpack.tf/profiles/76561198116724032#!/compare/1523059200/1523145600

Buyer: https://backpack.tf/profiles/76561198253239059#!/compare/1523145600/1523232000

No mini available, only sale was a quicksale.

Sale 3:

Sold for Bubbling Trucker's Topper + ~3 keys in pure/items

http://www.tf2outpost.com/trade/29577911 - No B/O

Seller: https://backpack.tf/profiles/76561198126985704#!/compare/1520208000/1520294400

Buyer: https://backpack.tf/profiles/76561198086747482#!/compare/1520121600/1520294400

Only sales I could find on the Topper were bulk or quicksales. Excluding.

Sale 4:

Bulk for Terror-Watt Falkirk

Seller: https://backpack.tf/profiles/76561198285540064#!/compare/1518393600/1518480000

Buyer: https://backpack.tf/profiles/76561198182213262#!/compare/1518393600/1518480000

Sale 5:

Sold for Abduction Head Full of Hot Air

http://www.tf2outpost.com/trade/29559110 - no B/O

Seller: https://backpack.tf/profiles/76561198182213262#!/compare/1518912000/1519084800

Buyer: https://backpack.tf/profiles/76561198080819275#!/compare/1518998400/1519084800

Without a B/O, this sale's probably gonna be a large outlier given the sellers on the Trucker.

Sale 6:

Bulk

Seller: https://backpack.tf/profiles/76561198080819275#!/compare/1518998400/1519084800

Buyer: https://backpack.tf/profiles/76561198257701328#!/compare/1518998400/1519084800

Steaming Hot Dogger:

https://backpack.tf/suggestion/5ad8ab72cf6c756cd80b8aa7

Seller at 12 on the classifieds:

https://i.imgur.com/ipQo9h4.png

Taking 12-15.

Was planning on pricing this, but we only have one usable sale at the moment.

Sellers:

~11.9 keys:

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

https://backpack.tf/item/6339478051

12 keys:

https://i.imgur.com/Sr137ua.png

https://backpack.tf/item/6705132051

Sales at:

9

10

11

12

https://i.imgur.com/d6n89BX.png - Buyers at 9+, excluding 9.

Going with 10-12.