Sale 1:

Sold for 31 keys

http://www.tf2outpost.com/trade/28816588 - Deleted B/O http://imgur.com/a/pGrIX - B/O of 35 (Credit to Moose)

Seller: http://backpack.tf/profiles/76561198004517334#!/compare/1489104000/1489190400

Buyer: http://backpack.tf/profiles/76561198301221585#!/compare/1488931200/1489190400

X = 31

Sale 2:

Sold for Stormy Charmer’s Chapeau (28) + 2 keys

Seller: http://backpack.tf/profiles/76561198271428863#!/compare/1490400000/1490486400

Buyer: http://backpack.tf/profiles/76561198120672630#!/compare/1490400000/1490486400

X = 30

Sale 3:

Sold for 25 keys in ~4 days

http://www.tf2outpost.com/trade/28800295 - B/O of 26

Seller: http://backpack.tf/profiles/76561198015384426#!/compare/1487980800/1488067200

Buyer: http://backpack.tf/profiles/76561198004517334#!/compare/1487894400/1487980800

X = 25

Sale 4:

Sold for 24 keys

http://www.tf2outpost.com/trade/28649094 - B/O of 26

Seller: http://backpack.tf/profiles/76561198019374940#!/compare/1486771200/1487635200

Buyer: http://backpack.tf/profiles/76561198015384426#!/compare/1487548800/1487635200

X = 24

Sale 5:

Quicksold for 24 keys

http://www.tf2outpost.com/trade/28835947 - B/O of 32

Seller: http://backpack.tf/profiles/76561198278474165#!/compare/1489795200/1489881600

Buyer: http://backpack.tf/profiles/76561198049072204#!/compare/1489795200/1489881600

X = 24

Sale 6:

Sold for Starstorm Insomnia Modest

Seller: http://backpack.tf/profiles/76561198120672630#!/compare/1490745600/1490832000

Buyer: http://backpack.tf/profiles/76561198126160370#!/compare/1490745600/1490832000

Would be better to price the Modest with this sale.

Sale 7:

Sold for Terror-Watt Festive Tree

http://www.tf2outpost.com/trade/28853882 - B/O of 36

Seller: http://backpack.tf/profiles/76561198126160370#!/compare/1490832000/1490918400

Buyer: http://backpack.tf/profiles/76561198144819017#!/compare/1490832000/1490918400

Can be used to update the tree.

Sellers:

35 keys:

http://i.imgur.com/JLUqwOE.png - 15 days

http://backpack.tf/u/76561198125791160

http://i.imgur.com/NANaV5f.png - 1 month, duped

http://backpack.tf/u/76561198090956917

http://www.tf2outpost.com/trade/28866330

36 keys:

http://i.imgur.com/HArFvsg.png - 30 days

http://backpack.tf/u/76561198034312547

48 keys:

http://www.tf2outpost.com/trade/27710018 - 1 year

http://backpack.tf/u/76561198126727520

Sales at:

24 (2x)

25

30

31

Sales at 24 and 25 sold in a short amount of time. I’m also certain that the seller of sale 4 lowered their price on outpost gradually.

Going with 30-31.