Sale 1:

Sold with a key + some ref for Kill-a-Watt Master’s Yellow Belt (24)

http://www.tf2outpost.com/trade/29431912 - No B/O

Seller: https://backpack.tf/profiles/76561198066207210#!/compare/1510704000/1510790400

Buyer: https://backpack.tf/profiles/76561198393784990#!/compare/1510531200/1510876800

X = 23

Sale 2:

Sold for 22 keys in ~3 days

Seller: https://backpack.tf/profiles/76561198263995096#!/compare/1511308800/1511395200

Buyer: https://backpack.tf/profiles/76561198042126891#!/compare/1511308800/1511395200

X = 22

Sale 3:

Sold for 21 keys in about a day

Seller: https://backpack.tf/profiles/76561198324846940#!/compare/1510704000/1510790400

Buyer: https://backpack.tf/profiles/76561198150531550#!/compare/1510444800/1510704000

X = 21

Sale 4:

Sold for 19 keys

Seller: https://backpack.tf/profiles/76561198306288794#!/compare/1506729600/1506816000

Buyer: https://backpack.tf/profiles/76561198302431811#!/compare/1506729600/1506816000

X = 19

Sale 5:

Sold for 19 keys

Seller: https://backpack.tf/profiles/76561198069493147#!/compare/1510790400/1510876800

Buyer: https://backpack.tf/profiles/76561198055847835#!/compare/1510790400/1510876800

X = 19

Sale 6:

Sold with 6 keys for Purple Confetti HWNN

Seller: https://backpack.tf/profiles/76561198393784990#!/compare/1510876800/1510963200

Buyer: https://backpack.tf/profiles/76561198019819713#!/compare/1510704000/1510963200

Should be used on the HWNN

Sale 7:

Bulk for Voltaic Spacemann

Seller: https://backpack.tf/profiles/76561198076588232#!/compare/1505865600/1506038400

Buyer: https://backpack.tf/profiles/76561198085628805#!/compare/1505952000/1506038400

Sale 8:

Bulk for Unusual Shotgun

Seller: https://backpack.tf/profiles/76561198085628805#!/compare/1506038400/1506124800

Buyer: https://backpack.tf/profiles/76561198306288794#!/compare/1506038400/1506124800

Sale 9:

Bulk for Eldritch Duck-Billed Platypus

Seller: https://backpack.tf/profiles/76561198143164913#!/compare/1505001600/1505088000

Buyer: https://backpack.tf/profiles/76561198069493147#!/compare/1505001600/1505088000

Sale 10:

Sold with 8 keys for Green Energy Ze Goggles

Seller: https://backpack.tf/profiles/76561198065356816#!/compare/1509062400/1509148800

Buyer: https://backpack.tf/profiles/76561198069388365#!/compare/1509062400/1509148800

Should be used on ze goggles

Sale 11:

Bulk for DBD Neckwear

Seller: https://backpack.tf/profiles/76561198272665457#!/compare/1510617600/1510876800

Buyer: https://backpack.tf/profiles/76561198114545227#!/compare/1510790400/1510876800

Sale 12:

Sold for 15 keys + 13 ref?

Seller: https://backpack.tf/profiles/76561198337734785#!/compare/1510617600/1510704000

Buyer: https://backpack.tf/profiles/76561198324846940#!/compare/1510617600/1510704000

I suspect that maybe CS:GO keys were added or something, I dunno.

Sellers:

24 keys:

https://i.imgur.com/o10XwkW.png - 1 day

https://i.imgur.com/zS2IbYm.png - young

25 keys:

https://i.imgur.com/eM7M9Th.png - 5 days

27 keys:

http://www.tf2outpost.com/trade/29446093 - 5 days

Offers:

http://www.tf2outpost.com/trade/29451677 - 1 day

Sales at:

19 (2x)

21

22

23

Sales at 22 and below sold kinda quickly, but excluding all of them wouldn’t be a good idea. I’ll set the low-end with the sale that took 3 days (22).

Going with 22-23.