Sale 1:

https://backpack.tf/profiles/76561198120672630#!/compare/1582502400/1582588800

https://backpack.tf/profiles/76561198134238543#!/compare/1582502400/1582588800

Sold with 6 keys for Duped Scorching Sack

Sack Mini:

https://pastebin.com/CEX9GmeV

Taking 31.5 keys

Total is 25.5 keys

sale 2:

https://backpack.tf/profiles/76561198134238543#!/compare/1582934400/1583020800

https://backpack.tf/profiles/76561198978621382#!/compare/1582588800/1583020800

Sold for Showstopper RPS(7) + MS BaL(3.3) + ~31 keys in sweets

Total is ~41 keys

sale 3:

https://backpack.tf/profiles/76561198978621382#!/compare/1583107200/1583193600

https://backpack.tf/profiles/76561198087806226#!/compare/1583020800/1583107200

Sold for ~22 keys

sale 4:

https://backpack.tf/profiles/76561198087806226#!/compare/1583539200/1583625600

https://backpack.tf/profiles/76561198249820130#!/compare/1583539200/1583625600

Sold for 28 Keys

Sale 5:

https://backpack.tf/profiles/76561198249820130#!/compare/1584144000/1584230400

https://backpack.tf/profiles/76561198076205439#!/compare/1584144000/1584230400

Bulk

sale 6:

https://backpack.tf/profiles/76561198076205439#!/compare/1584576000/1584662400

https://backpack.tf/profiles/76561198334946156#!/compare/1584489600/1584576000

Sold for CH Baker

Baker Mini:

https://backpack.tf/suggestion/5eab6168ff957951f9120e3e

Suggestion for 23 keys

sale 7:

https://marketplace.tf/items/tf2/200;5;u702;w3;pk235

$49.49 / $1.68 = 29.46 keys

https://backpack.tf/item/8229282451

Total sales @:

22, 23, 26, 28, 29, 41 keys

https://backpack.tf/classifieds?page=5&item=Skull%20Study%20%7C%20Scattergun%20%28Field-Tested%29&quality=15&tradable=1&craftable=1&australium=-1&particle=702&killstreak_tier=0

Buyers up to ~25 keys,

taking 26 - 29 keys.