Sales supporting the price:

Sale 1:

Sold for 15 keys

http://www.tf2outpost.com/trade/27896557

Seller: http://backpack.tf/profiles/76561198091120725/#!/compare/1456732800/1456905600

Buyer: http://backpack.tf/profiles/76561198129879465/#!/compare/1456300800/1456819200

X = 15

Sale 2: (Dupe Sale)

Sold for:

Strange Festive Killstreak Knife with ~2.5 keys in parts (10)

Strange Killstreak Shotgun (0.4)

Strange Spec. KS Carbonado Scattergun with ~1 key in parts (2)

Black Double-cross Comm (1.8)

Bruiser's Bandana (0.95)

Strange Rescue Ranger (0.15)

Lady Killer (0.7)

No outpost link available

Seller: http://backpack.tf/profiles/76561198151791447/#!/compare/1455955200/1456041600

Buyer: http://backpack.tf/profiles/76561198091821463/#!/compare/1455955200/1456041600

X = 10 + 2 + 1.8 + 0.95 + 0.7 + 0.4 + 0.15

X = 16

Sale 3:

Sold for Factory New Killer Bee Scattergun

No outpost link available

Seller: http://backpack.tf/profiles/76561198044664114/#!/compare/1456905600/1456992000

Buyer: http://backpack.tf/profiles/76561198127396514/#!/compare/1455609600/1457424000

X = 14

Sale 4:

Sold in a day for 12 keys + Virtual Viewfinder painted 'after eight'

http://www.tf2outpost.com/trade/27865620 - B/O of 14

Seller: http://backpack.tf/profiles/76561198137024023/#!/compare/1455868800/1455955200

Buyer: http://backpack.tf/profiles/76561198071334162/#!/compare/1455868800/1455955200

Seller with same paint for 7.33 ref in classifieds

X = 12 + 0.4

X = 12.4

Rounding to 12

Additional Sales:

Sale 5: (Dupe sale)

Sold with Strange Double Dynamite for Duped Steaming Hot Rod

No outpost link available

Seller: http://backpack.tf/profiles/76561198091821463/#!/compare/1455955200/1456041600

Buyer: http://backpack.tf/profiles/76561198044664114/#!/compare/1455955200/1456041600

The Steaming Hot Rod was lacking valid sales, having only 3-4 sales that could be distinguished. One of the sales was for 9 keys in items (low), one was a quicksale for 13 keys and 2 sales were for outdated unusuals that couldn't be updated due to lack of valid sales. Therefore, it would be better to use this suggestion to update the Hot Rod, then the Hot Rod to possibly update the other two unusuals.

Sale 6:

Most likely sold for items for other games

No outpost link available

Seller: http://backpack.tf/profiles/76561198116527261/#!/compare/1452240000/1457251200

Buyer: http://backpack.tf/profiles/76561198051263429/#!/compare/1455436800/1455523200

Sale 7:

Don't know what was involved

http://www.tf2outpost.com/trade/27428502 - wanted to pay bulk for a Miami Nights Crone's Dome

Seller: http://backpack.tf/profiles/76561198115783287/#!/compare/1453795200/1453881600

Buyer: http://backpack.tf/profiles/76561198085300335/#!/compare/1453536000/1453968000

Sale 8:

Looks like a bulk sale for other game items

No Outpost link available

Seller: http://backpack.tf/profiles/76561198164755415/#!/compare/1455955200/1456905600

Buyer: http://backpack.tf/profiles/76561198209105920/#!/compare/1453968000/1456041600

Sale 9:

Nothing in return, according to compare links

http://www.tf2outpost.com/trade/27878207 - No B/O

Seller: http://backpack.tf/profiles/76561198209105920/#!/compare/1456041600/1456128000

Buyer: http://backpack.tf/profiles/76561198059781957/#!/compare/1456041600/1456128000

Sale 10:

Not sure what it sold for

No outpost link available

Seller: http://backpack.tf/profiles/76561198129879465/#!/compare/1456992000/1457078400

Buyer: http://backpack.tf/profiles/76561198148696335/#!/compare/1456992000/1457164800

Sale 11:

Probably gambled away

No outpost link available

Seller: http://backpack.tf/profiles/76561198195205727/#!/compare/1455091200/1455177600

Buyer: http://backpack.tf/profiles/76561198200886517/#!/compare/1455091200/1455177600

Sales at:

12 (pure, sold in a day)

14

15 (pure)

16

Going with 14-16