Classifieds at the time of posting this suggestion.

The age of the listing(s) are shown in the screenshot(s) rather than the last bump.

Unsolds and item histories are presented in chronological order according to the screenshot(s).

x2 for sale at 1.2 Keys - http://i.imgur.com/TgsZ7iY.png

Unsold for 15 minutes http://backpack.tf/item/1845188308

Unsold for 1 day http://backpack.tf/item/1728398825

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x1 for sale at 1.25 Keys - http://i.imgur.com/QODfdrd.png

Unsold for 5 days http://backpack.tf/item/1870382250

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x4 for sale at 1.3 Keys - http://i.imgur.com/vRJWlIs.png

Unsold for 8 days http://backpack.tf/item/1641986366

Unsold for 5 days(Parts Attached) http://backpack.tf/item/1681775691

Unsold for 16 days http://backpack.tf/item/1732561904

Unsold for 2 months http://backpack.tf/item/3538993481

Outpost sellers.

http://www.tf2outpost.com/trade/28477144 - 1.3 Keys - Unsold for 3 days.

http://www.tf2outpost.com/trade/28464823 - 1.3 Keys - Unsold for 1 week.

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http://www.tf2outpost.com/trade/28454137 - 1.3 Keys - Unsold for 1 week - Autobumper - Item swapped inventories but this makes no sense;

http://backpack.tf/profiles/76561198040230289#!/compare/1467331200/1472515200

Discounting.

I am excluding all trades on Outpost that haven't been bumped in 1 day or more.