Sale 1:

Sold for 20 keys

Seller: https://backpack.tf/profiles/76561198156255538#!/compare/1503878400/1503964800

Buyer: https://backpack.tf/profiles/76561198038751161#!/compare/1503878400/1503964800

X = 20

Sale 2:

Sold for Max’s (19)

Seller: https://backpack.tf/profiles/76561198155320889#!/compare/1507161600/1507248000

Buyer: https://backpack.tf/profiles/76561198073613398#!/compare/1506816000/1507334400

X = 19

Sale 3:

Sold for 17 keys + ~1 key in items

http://www.tf2outpost.com/trade/29361152 - B/O of 21

Seller: https://backpack.tf/profiles/76561198202921439#!/compare/1505001600/1505088000

Buyer: https://backpack.tf/profiles/76561198083465346#!/compare/1505001600/1505088000

X = 18

Sale 4:

Sold for 18 keys

Seller: https://backpack.tf/profiles/76561198083465346#!/compare/1507161600/1507420800

Buyer: https://backpack.tf/profiles/76561198064538918#!/compare/1507420800/1507680000

X = 18

Sale 5:

Sold for Collector’s Razorback (5) + 16 keys

https://imgur.com/a/mS8vH - B/O of 18, seller confirms sale

Seller: https://backpack.tf/profiles/76561198144346135#!/compare/1507248000/1507334400

Buyer: https://backpack.tf/profiles/76561198193881166#!/compare/1507248000/1507334400

X = 18 (Capped by B/O)

Sale 6:

Sold for ~18 keys in pure/items

No outpost

Seller: https://backpack.tf/profiles/76561197994697258#!/compare/1505174400/1505260800

Buyer: https://backpack.tf/profiles/76561198110829479#!/compare/1505174400/1505260800

X = 18

Sale 7:

Sold with 2 keys for Cloud 9 Fruit Shoot

Seller: https://backpack.tf/profiles/76561198038751161#!/compare/1504656000/1504742400

Buyer: https://backpack.tf/profiles/76561198202921439#!/compare/1504656000/1504742400

Can be used on the Fruit.

Sale 8:

Sold for Purple Confetti Rebel Rouser

Seller: https://backpack.tf/profiles/76561198259033965#!/compare/1508284800/1508716800

Buyer: https://backpack.tf/profiles/76561198024925599#!/compare/1508716800/1508803200

Should be used on the Rouser.

Sellers:

20 keys:

https://i.imgur.com/ot25BBL.png - 22 days

22 keys:

https://i.imgur.com/Zci1nUA.png - 13 days

Sales at:

18 (4x)

19

20

Going with 18-20.