Sale #1:

https://backpack.tf/profiles/76561198121939022#!/compare/1548460800/1548547200

Scam?

----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

Sale #2:

https://marketplace.tf/items/30762;5;u3019

Sold for $14.54.

$14.54 / $1.80 = ~8 keys

8 keys

----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

Sale #3:

https://backpack.tf/profiles/76561198210225228#!/compare/1547424000/1547510400

Sold for 7 keys.

7 keys

----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

Sale #4:

https://backpack.tf/profiles/76561198004563193#!/compare/1548028800/1548115200

Bulk.

----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

Sale #5:

https://backpack.tf/profiles/76561198271567859#!/compare/1549152000/1549843200

Sold for 6 keys.

6 keys

Sales:

6, 7, 8. Going with 6 - 7 keys, unsolds at 7 keys for multiple months shows 8 keys is likely an outlier.