Sale 1:

Sold for Orbiting Fire Reggaelator (15.5, aged seller at 14, taking 15) + ~3 keys in pure/items

No outpost

Seller: https://backpack.tf/profiles/76561197961172123#!/compare/1501372800/1501459200

Buyer: https://backpack.tf/profiles/76561198209202551#!/compare/1501372800/1501459200

X = 18

Sale 2:

Sold with cheap items for Orbiting Planets Desert Marauder (14.5, aged sellers at 13, taking 14) + 1 key + Strange Spec. KS Festive Black Box (~2)

No outpost

Seller: https://backpack.tf/profiles/76561198029437726#!/compare/1503619200/1503705600

Buyer: https://backpack.tf/profiles/76561198139732126#!/compare/1503619200/1503705600

X = 17

Sale 3:

Sold with 1 key + < 0.5 keys in items for Logo Blast Defense (18)

http://www.tf2outpost.com/trade/29347624 - No B/O

Seller: https://backpack.tf/profiles/76561198139732126#!/compare/1503792000/1503878400

Buyer: https://backpack.tf/profiles/76561198127508395#!/compare/1503792000/1503878400

X = 17

Sale 4:

Sold for 15 keys

No outpost

Seller: https://backpack.tf/profiles/76561198100773215#!/compare/1502323200/1502409600

Buyer: https://backpack.tf/profiles/76561198075510322#!/compare/1502323200/1502409600

X = 15

Sale 5:

Sold for 14 keys

http://www.tf2outpost.com/trade/29236056 - Deleted B/O

Seller: https://backpack.tf/profiles/76561198067575136#!/compare/1497916800/1498003200

Buyer: https://backpack.tf/profiles/76561198053837781#!/compare/1497916800/1498003200

X = 14

Sale 6:

Quicksold for 12 keys

No outpost

Seller: https://backpack.tf/profiles/76561198104667663#!/compare/1498521600/1498608000

Buyer: https://backpack.tf/profiles/76561198309937181#!/compare/1498521600/1498608000

X = 12

Sale 7:

Bulk for stuff

Seller: https://backpack.tf/profiles/76561198070740519#!/compare/1498348800/1498521600

Buyer: https://backpack.tf/profiles/76561198329291302#!/compare/1498435200/1498521600

Sale 8:

Bulk for Purple Energy Harmburg

Seller: https://backpack.tf/profiles/76561198129666631#!/compare/1503100800/1503187200

Buyer: https://backpack.tf/profiles/76561198208548647#!/compare/1503187200/1503273600

Sale 9:

Bulk for Peace Sign Modest

Seller: https://backpack.tf/profiles/76561198088057122#!/compare/1503532800/1503619200

Buyer: https://backpack.tf/profiles/76561198029437726#!/compare/1502841600/1503619200

Sale 10:

Bulk for Time Warp L’inspecteur

Seller: https://backpack.tf/profiles/76561198167632755#!/compare/1499817600/1499904000

Buyer: https://backpack.tf/profiles/76561197961172123#!/compare/1499817600/1499904000

Sellers:

15 keys:

http://www.tf2outpost.com/trade/29261093 - 1 month, lowered from 16:

http://www.tf2outpost.com/trade/29233433 and

http://www.tf2outpost.com/trade/29191378 - 3 months ago here

https://backpack.tf/item/863824540 - 4 months total

16 keys:

http://i.imgur.com/OoWxfmT.png - 10 days

http://i.imgur.com/GIoBjtX.png - 1 day

Sales at:

12

14

15

17 (2x)

18

12 quicksold. Excluding 12.

Sales at 17 and 18 would most likely be lower if we knew the B/O. Also, the 4-month-old seller at 15-16 proves that it doesn’t sell well for more than 16. Should be right to go with the pure sales here anyways. Excluding 17 and 18.

Going with 14-15.