Sale 1:

https://backpack.tf/profiles/76561198311498888#!/compare/1535500800/1535587200

https://backpack.tf/profiles/76561198426854700#!/compare/1523664000/1535673600

Untrace.

Sale 2:

https://backpack.tf/profiles/76561198337734785#!/compare/1531440000/1531526400

https://backpack.tf/profiles/76561198132188858#!/compare/1531526400/1531612800

Sold for 9 keys + 9 ref (ID Match)

Sale 3:

https://backpack.tf/profiles/76561198132188858#!/compare/1532736000/1532822400

https://backpack.tf/profiles/76561198154864046#!/compare/1532649600/1532736000

Sold for 6 keys? Not using.

Sale 4:

https://backpack.tf/profiles/76561198154864046#!/compare/1532736000/1532822400

https://backpack.tf/profiles/76561198296350441#!/compare/1532736000/1532822400

Sold with 4 keys for G Fetti Naggen(15)

Total is 11 keys

Sale 5:

https://backpack.tf/profiles/76561198296350441#!/compare/1532736000/1532822400

https://backpack.tf/profiles/76561198349373309#!/compare/1532736000/1532822400

Bulky

Sale 6:

https://backpack.tf/profiles/76561198349373309#!/compare/1532822400/1532908800

https://backpack.tf/profiles/76561198204215085#!/compare/1532822400/1532908800

Untrace / bulk

Sale 7:

https://backpack.tf/profiles/76561198068701324#!/compare/1532390400/1532908800

https://backpack.tf/profiles/76561198836204190#!/compare/1532736000/1532822400

Sold for 8 keys

Sale 8:

https://backpack.tf/profiles/76561198836204190#!/compare/1532822400/1532908800

https://backpack.tf/profiles/76561198101556932#!/compare/1532649600/1532908800

Sold for 9 keys

Sale 9:

https://backpack.tf/profiles/76561198101556932#!/compare/1532995200/1533081600

https://backpack.tf/profiles/76561198132951873#!/compare/1532822400/1533081600

Untrace.

Sale 10:

https://backpack.tf/profiles/76561198217891717#!/compare/1532822400/1533168000

Sold for 9 keys + ToD ticket

Total is ~9.5 keys

Sale 11:

https://backpack.tf/profiles/76561198217891717#!/compare/1533168000/1533254400

https://backpack.tf/profiles/76561198344557661#!/compare/1533168000/1533254400

Bulky

Sale 12:

https://backpack.tf/profiles/76561198344557661#!/compare/1533254400/1533686400

Sold for 8 keys

Total sales @:

8, 8, 9, 9.26, 9.5, 11

https://i.imgur.com/MncMT2s.jpg

Buyers up to 8.35 keys

Unsold for a month at 10 keys

https://backpack.tf/item/2009622983

Let's go with 9 - 9.5 keys