Sale 1:

Sold for Cloud 9 Pom-Pommed Provocateur (Mini at 16.5 below) + 2 keys

http://www.tf2outpost.com/trade/28636223 - B/O of 20

Seller: http://backpack.tf/profiles/76561198032176942#!/compare/1480377600/1480464000

Buyer: http://backpack.tf/profiles/76561198121220328#!/compare/1480377600/1480464000

X = 19

Sale 2:

Sold for Spec. KS Aussie Flamethrower (16) + Revolver Skin (2)

No outpost

Seller: http://backpack.tf/profiles/76561198192602363#!/compare/1476230400/1476403200

Buyer: http://backpack.tf/profiles/76561198074387943#!/compare/1476057600/1476403200

X = 18

Sale 3:

Sold for Peace Sign Fur-Lined Fighter (Mini at 20 below) + <0.5 keys in items

http://www.tf2outpost.com/trade/28628020 - B/O of 17

Seller: http://backpack.tf/profiles/76561198105583712#!/compare/1481068800/1481500800

Buyer: http://backpack.tf/profiles/76561198118148699#!/compare/1481414400/1481500800

X = 17 (Capped by B/O)

Sale 4:

Sold with 2 ToD Tickets (1) for Killstreak Aussie Knife (~19 at the time)

http://www.tf2outpost.com/trade/28524746 - B/O of 17

Seller: http://backpack.tf/profiles/76561198157337863#!/compare/1475884800/1475971200

Buyer: http://backpack.tf/profiles/76561198273936453#!/compare/1475884800/1475971200

X = 17 (Capped by B/O)

Sale 5:

Sold in a day for 15 keys

http://www.tf2outpost.com/trade/28627657 - No B/O

Seller: http://backpack.tf/profiles/76561198279458953#!/compare/1479686400/1480032000

Buyer: http://backpack.tf/profiles/76561198105583712#!/compare/1479945600/1480032000

X = 15

Sale 6:

Quicksold with 10 ref for 15 keys

http://www.tf2outpost.com/trade/28546015 - B/O of 14.5

Seller: http://backpack.tf/profiles/76561198048936503#!/compare/1476489600/1476576000

Buyer: http://backpack.tf/profiles/76561198201058206#!/compare/1475971200/1476662400

X = 15

Sale 7:

Sold for Circling Peace Sign Sola Topi (13)

No outpost

Seller: http://backpack.tf/profiles/76561198180715845#!/compare/1476748800/1477008000

Buyer: http://backpack.tf/profiles/76561198002757046#!/compare/1476662400/1476748800

X = 13

Sale 8:

Sold for Bubbling Virtual Reality Headset + 2 keys

http://www.tf2outpost.com/trade/28545341 - B/O of 18

Seller: http://backpack.tf/profiles/76561198074387943#!/compare/1476403200/1476576000

Buyer: http://backpack.tf/profiles/76561198048936503#!/compare/1476489600/1476576000

Given that there are sellers for cheaper on the Headset, this sale would probably be around 15 keys, which, based on the quicksales at 15, would be too low.

Sale 9:

Bulk for Haunted Ghosts Defiant Spartan

No outpost

Seller: http://backpack.tf/profiles/76561198272072941#!/compare/1478736000/1478822400

Buyer: http://backpack.tf/profiles/76561198074924284#!/compare/1478649600/1478736000

Sale 10:

Sold for Orbiting Fire L’Homme Burglerre

http://www.tf2outpost.com/trade/28604072 - No B/O

Seller: http://backpack.tf/profiles/76561198211445756#!/compare/1479081600/1479254400

Buyer: http://backpack.tf/profiles/76561198279458953#!/compare/1479168000/1479254400

Might be better to update the Burg with this sale, due to the lack of B/O here, as well as the cheaper sellers on the Burg

Pom-Pommed Provocateur Mini:

http://backpack.tf/suggestion/5850b6bac4404533271f9e1e

Peace Sign Fur-Lined Fighter Mini:

http://backpack.tf/suggestion/5850baa7e338774ad30d998f

Sellers:

16 keys:

http://i.imgur.com/9hKj2iY.png - 8 days

http://backpack.tf/u/76561197982127154

http://www.tf2outpost.com/trade/28649909

18 keys:

http://i.imgur.com/K0TrT1g.png - 6 days

http://backpack.tf/u/76561198023542389

http://www.tf2outpost.com/trade/28611031 - 3 weeks, most likely lowered 6 days ago

19 keys:

http://i.imgur.com/2ccT858.png - 1 month

http://backpack.tf/u/76561198074924284

Sales:

13

15 (2x)

17 (2x)

18

19

Sales at 15 quicksold. Excluding 15 and lower.

Seller at 16 for at least a week. Including 16 in the range.

Going with 16-19