All credits to gbsfranca, just forgot to resuggest!

hat 1

sale 1

https://backpack.tf/profiles/76561198070634279#!/compare/1523145600/1523404800

https://marketplace.tf/items/480;5;u39

sold for $50 / $1.85 = ~26 keys

hat 2

sale 1

https://backpack.tf/profiles/76561198156102793#!/compare/1522886400/1523059200

https://backpack.tf/profiles/76561198112155547#!/compare/1522972800/1523059200

sold with a key pure and a Schadenfreude for a Disco Beat Down Airdog (mini)

sale 2

https://backpack.tf/profiles/76561198112155547#!/compare/1523836800/1523923200

https://backpack.tf/profiles/76561198120920913#!/compare/1523923200/1524009600

sold for a Vivid Plasma Glengarry Bonnet and a key in metal

sale 3

https://backpack.tf/profiles/76561198169916882#!/compare/1524787200/1524873600

https://backpack.tf/profiles/76561198054758757#!/compare/1524700800/1524787200

sold to buy order & untraceable

Vivid Plasma Glengarry Bonnet “mini”

https://backpack.tf/suggestion/5b22ddf144325a59401fa979

taking 21 keys

Disco Beat Down Airdog “mini”

https://backpack.tf/suggestion/5b362dc9cf6c754fea78fe65

taking 17 keys

Taking 16 - 22