Sale 1:

https://backpack.tf/profiles/76561198001766492#!/compare/1565136000/1565222400

https://backpack.tf/profiles/76561198048851745#!/compare/1564963200/1565136000

QS

sale 2:

https://backpack.tf/profiles/76561198048851745#!/compare/1565136000/1565222400

https://backpack.tf/profiles/76561198855785526#!/compare/1560124800/1565654400

Sold for 8 keys

Sale 3:

https://backpack.tf/profiles/76561198855785526#!/compare/1566518400/1566604800

https://backpack.tf/profiles/76561198089253101#!/compare/1566518400/1566604800

Sold for DP Plat Pickel

Pickel Mini:

https://backpack.tf/suggestion/5da09379d3817211137e7b77

Suggestion for 7 keys

Sale 4:

https://backpack.tf/profiles/76561198302622799#!/compare/1564012800/1564099200

https://backpack.tf/profiles/76561198312950883#!/compare/1563926400/1564099200

untrace

Sale 5:

https://backpack.tf/profiles/76561198312950883#!/compare/1564185600/1564272000

https://backpack.tf/profiles/76561198323565601#!/compare/1564185600/1564272000

Sold for 7 keys (QS)

sale 6:

https://backpack.tf/profiles/76561198418193004#!/compare/1570233600/1570320000

https://backpack.tf/profiles/76561198376925491#!/compare/1570233600/1570320000

Sold with ~0.49 keys in sweets for DBD Mullet

Mullet Mini:

https://backpack.tf/suggestion/5da095e8d3817213ee19bdbb

Suggestion for 10 keys

Total is ~9.5 keys

Sale 7:

https://marketplace.tf/items/tf2/30327;5;u33

$18.19 / $1.81 = 10.05 keys

https://backpack.tf/item/7234404102

Total sales @:

7, 7, 8, 9.5, 10 keys

buyers up to ~6.5 keys,

sellers at 10 keys,

taking 7 - 10 keys