Sale 1-4:

https://marketplace.tf/items/tf2/30978;5;u32

$17 / $1.77 = 9.60 keys

$10.2 / $1.76 = 5.80 keys

$8.3 / $1.69 = 4.91 keys

$14.99 / $1.75 = 8.57 keys

Sale 5:

untrace

https://backpack.tf/profiles/76561198341171690#!/compare/1581897600/1581984000

https://backpack.tf/profiles/76561198242571452#!/compare/1581811200/1581984000

Sale 6:

5 keys + 3 ref

https://backpack.tf/profiles/76561198242571452#!/compare/1582070400/1582502400

https://backpack.tf/profiles/76561198337734785#!/compare/1582416000/1582502400

Sale 7:

untrace

https://backpack.tf/profiles/76561198337734785#!/compare/1586304000/1586390400

https://backpack.tf/profiles/76561198985910282#!/compare/1586563200/1586649600

Sale 8:

bulk

https://backpack.tf/profiles/76561198017911489#!/compare/1585612800/1585699200

https://backpack.tf/profiles/76561198088551406#!/compare/1585612800/1585699200

Sale 9:

bulk

https://backpack.tf/profiles/76561198088551406#!/compare/1585612800/1585699200

https://backpack.tf/profiles/76561198056974324#!/compare/1585612800/1585699200

Sale 10:

bulk

https://backpack.tf/profiles/76561198056974324#!/compare/1585958400/1586044800

https://backpack.tf/profiles/76561198031743044#!/compare/1585958400/1586044800

Sale 11:

6.7 keys

6 keys + 38 ref

https://backpack.tf/profiles/76561198031743044#!/compare/1586044800/1586390400

https://backpack.tf/profiles/76561198032176942#!/compare/1586304000/1586563200

Sale 12:

untrace

https://backpack.tf/profiles/76561198119778504#!/compare/1520812800/1582675200

https://backpack.tf/profiles/76561198079989511#!/compare/1582588800/1582675200

Sale 13:

untrace

https://backpack.tf/profiles/76561198079989511#!/compare/1582675200/1582761600

https://backpack.tf/profiles/76561198026462419#!/compare/1582675200/1582761600

many same day sales cant really trace them

https://backpack.tf/item/8508326468

Sale 14:

untrace

https://backpack.tf/profiles/76561199011873091#!/compare/1582675200/1582761600

https://backpack.tf/profiles/76561198107654171#!/compare/1582675200/1582761600

Sale 15:

untrace

https://backpack.tf/profiles/76561198107654171#!/compare/1582675200/1582761600

https://backpack.tf/profiles/76561198341171690#!/compare/1582675200/1582761600

==============================================================================

Sales:

5, 5, 6, 6.5, 8.5, 9.5

many buyers at 5+ keys: https://imgur.com/a/hOhbkPL

3+ weeks unsold at 7k + 22ref: https://imgur.com/a/Fl8MLyP - https://imgur.com/a/tCgLu5z

before that it was unsold since 1st march at 7k + 36ref: https://imgur.com/a/0kDJLvC - https://backpack.tf/item/8508326468