#Squad-1, ~Zeckatz.

Sale 1: ~16 Keys Pure.

https://backpack.tf/profiles/76561198847672167#!/compare/1553299200/1553385600

https://backpack.tf/profiles/76561198162546850#!/compare/1553212800/1553385600

Sale 2: Bulk.

https://backpack.tf/profiles/76561198162546850#!/compare/1554249600/1554508800

https://backpack.tf/profiles/76561198080179568#!/compare/1554422400/1554508800

Sale 3: using there (aces muffs)

https://backpack.tf/profiles/76561198080179568#!/compare/1556236800/1556323200

https://backpack.tf/profiles/76561198334414559#!/compare/1556236800/1556323200

Sale 4: ~14 Keys. (QS)

https://backpack.tf/profiles/76561198258042183#!/compare/1554163200/1554940800

https://backpack.tf/profiles/76561198928452311#!/compare/1554854400/1554940800

Sale 5: Transfer?

https://backpack.tf/profiles/76561198928452311#!/compare/1554940800/1555113600

https://backpack.tf/profiles/76561198403141575#!/compare/1554940800/1555113600

Sale 6: Bulk.

https://backpack.tf/profiles/76561198403141575#!/compare/1555286400/1555718400

https://backpack.tf/profiles/76561198192602363#!/compare/1555632000/1555718400

Sale 7: ~14 Keys. (QS)

https://backpack.tf/profiles/76561198031051413#!/compare/1553385600/1553472000

https://backpack.tf/profiles/76561198928452311#!/compare/1553385600/1553472000

Sale 8: ~16 Keys Pure.

https://backpack.tf/profiles/76561198928452311#!/compare/1553817600/1553904000

https://backpack.tf/profiles/76561198399104205#!/compare/1553472000/1553904000

Sale 9: Untrace/QS?

https://backpack.tf/profiles/76561198399104205#!/compare/1554681600/1554854400

https://backpack.tf/profiles/76561198317418604#!/compare/1554595200/1554768000

Sale 10: ~17 Keys Pure.

https://backpack.tf/profiles/76561198385727483#!/compare/1552262400/1552348800

https://backpack.tf/profiles/76561198132932617#!/compare/1552262400/1552348800

Sale 11: ~17 Keys Pure.

https://backpack.tf/profiles/76561198080179568#!/compare/1553731200/1553817600

https://backpack.tf/profiles/76561198077950315#!/compare/1553731200/1553817600

Sale 12: ~16 Keys?

https://backpack.tf/profiles/76561198077950315#!/compare/1554422400/1554508800

https://backpack.tf/profiles/76561198370572974#!/compare/1554508800/1554595200

Sale 13: Bulk.

https://backpack.tf/profiles/76561198370572974#!/compare/1555891200/1556064000

https://backpack.tf/profiles/76561198055622215#!/compare/1555891200/1556064000

Sale 14: ~17 Keys.

Sold For Blizzardy Storm Flipped Trilby (17)

https://backpack.tf/profiles/76561198055622215#!/compare/1556236800/1556323200

https://backpack.tf/profiles/76561198278215661#!/compare/1556150400/1556323200

Sale 15: ~18 Keys.

Sold With 1 Key For Aces High Neckwear Headwear

https://backpack.tf/profiles/76561198278215661#!/compare/1556841600/1556928000

https://backpack.tf/profiles/76561198118534054#!/compare/1556582400/1556841600

Marketplace.tf Sales:

https://marketplace.tf/items/324;5;u61

Sale 16: ~21 Keys. (High)

Apr 6

$36.99 / $1.79 = 20.66 keys

Sale 17: Low.

Apr 10

$22.58 / $1.77 = 12.76 keys

Sale 18: ~19 Keys. (Excluding)

Apr 27

$34.95 / $1.8 = 19.42 keys

Including Sales: 16/16/16/17/17/17/18

Going With 16-18 Keys.