Mini!

Sale 1: https://backpack.tf/profiles/76561198125791160#!/compare/1511136000/1511222400

https://backpack.tf/profiles/76561198161032944#!/compare/1511136000/1511222400

Bulk.

Sale 2: https://backpack.tf/profiles/76561198135418759#!/compare/1514678400/1514764800

https://backpack.tf/profiles/76561198125791160#!/compare/1514592000/1514678400

33 keys pure.

Sale 3: https://backpack.tf/profiles/76561198073918830#!/compare/1511049600/1511827200

https://backpack.tf/profiles/76561198092964212#!/compare/1511740800/1511827200

Sold with like 1 key in adds for a clean Power Surge Flipped Trilby (24 keys) + 4 keys

(24 + 4) - 1 = 27

Sale 4: https://backpack.tf/profiles/76561198200270154#!/compare/1512172800/1512259200

https://backpack.tf/profiles/76561198073918830#!/compare/1512000000/1512259200

25 pure + a key in adds

25 + 1 = 26

Sale 5: https://backpack.tf/profiles/76561198126842843#!/compare/1512950400/1513036800

https://backpack.tf/profiles/76561198200270154#!/compare/1512604800/1512950400

Use on the Kniff.

Sale 6: https://backpack.tf/profiles/76561198123899074#!/compare/1512864000/1512950400

https://backpack.tf/profiles/76561198126842843#!/compare/1512950400/1513036800

Sold with 3 keys in adds for a clean Miami Nights Troublemaker's Tossle Cap (29 keys)

29 - 3 = 26

Mini for the Tossle: https://backpack.tf/suggestion/5a621ef7cf6c7569ca354700

Sale 7: https://backpack.tf/profiles/76561198278629188#!/compare/1513987200/1514073600

https://backpack.tf/profiles/76561198123899074#!/compare/1513987200/1514073600

30 keys pure.

Sales: 33, 27, 26, 26 and 30. 26-33 seems easily perfect.