Sale 1:

Sold for 15 keys

Seller: https://backpack.tf/profiles/76561198043936328#!/compare/1511827200/1511913600

Buyer: https://backpack.tf/profiles/76561198129375919#!/compare/1511827200/1511913600

X = 15

Sale 2:

Bulk for Logo Vintage Tyrolean

Seller: https://backpack.tf/profiles/76561198054361771#!/compare/1509753600/1509840000

Buyer: https://backpack.tf/profiles/76561198043936328#!/compare/1509753600/1509840000

Sale 3:

Bulk for Cloud 9 Human Cannonball

Seller: https://backpack.tf/profiles/76561198044049846#!/compare/1511654400/1511913600

Buyer: https://backpack.tf/profiles/76561198112406131#!/compare/1511827200/1511913600

Sale 4:

Bulk for Bubbling Coldsnap Cap

Seller: https://backpack.tf/profiles/76561198112406131#!/compare/1511913600/1512000000

Buyer: https://backpack.tf/profiles/76561198065118999#!/compare/1511913600/1512000000

Sale 5:

Sold with ~1 key in items for Orbiting Fire Pickelhaube

Seller: https://backpack.tf/profiles/76561198402901200#!/compare/1512259200/1512345600

Buyer: https://backpack.tf/profiles/76561198054945991#!/compare/1512259200/1512345600

Should be used on the Pickel.

Sellers:

14 keys:

https://i.imgur.com/2xN4HpO.png - young

https://i.imgur.com/kmKKp7s.png - 1 day

Seller on outpost already sold.

Sales at:

15

2 sellers at 14.

Going with 14-15.