I didn't expect this.

Sale 1

Sold for 22 keys (sort by time)

http://backpack.tf/profiles/76561198042938501#!/compare/1470960000/1471046400

http://www.tf2outpost.com/trade/28354135 ----- B/O was 22 keys

=======> 22 keys

======================================================

Sale 2

Sold for ~22 keys in mixed sweets.

http://backpack.tf/profiles/76561198040923298#!/compare/1471824000/1472169600

http://www.tf2outpost.com/trade/28416258 ----- No B/O

=======> 22 keys

======================================================

Sale 3

Sold for 20 keys

http://backpack.tf/profiles/76561198091288681#!/compare/1472688000/1472774400

http://www.tf2outpost.com/trade/28445367 ----- B/O was 22 keys

=======> 20 keys

======================================================

Sellers

- http://imgur.com/a/zJqXq ----- 27 keys

Summary

- Sales for 20, 22, 22.

Going with 20-22 keys. Criticism appreciated!