Mini.

95% of the credits to Ramen and Squash.

Well, this is dumb easy.

Sale 1: https://marketplace.tf/items/31000;5;u116 - 129.99/1.70 = ~76 (apparently sale was closer to 80: https://i.imgur.com/WPCJAa6.png)

Sale 2: https://marketplace.tf/items/31000;5;u116 - 124/1.79 = ~69

Sale 3: https://marketplace.tf/items/31000;5;u116 - 120/1.75 = ~69

Sale 4: https://marketplace.tf/items/31000;5;u116 - 120/1.80 = ~67

Sale 5: https://backpack.tf/profiles/76561198107260155#!/compare/1542585600/1542672000

https://backpack.tf/profiles/76561198321556119#!/compare/1542585600/1542758400

Sold for a Blizzardy Storm Blighted Beak (68 keys)

Mini for the Beak:

Sale 1: https://backpack.tf/profiles/76561198128838220#!/compare/1543622400/1543795200

Sold for 66 keys

Sale 2: https://backpack.tf/profiles/76561198107260155#!/compare/1545004800/1545177600

Sold for 70 keys (traded one for ref immediately after)

Credits to Bekfust: https://gyazo.com/026fcd8b15cc1662ffa3ceee5ade0106

Taking 66-70 (68).

Sale 6: https://backpack.tf/profiles/76561198148983419#!/compare/1546473600/1546560000

https://backpack.tf/profiles/76561198326603957#!/compare/1546387200/1546473600

Doesn't seems like the items traded for the unusual are shown here??

Sale 7: https://backpack.tf/profiles/76561198326603957#!/compare/1546473600/1546560000

Sold for 31 keys + Aussie minigun ( 18 keys ) = 49 keys

Seems like a quicksale? despite the huge price different from the other sales, and that it was sold in under 2 days

Sale 8: https://backpack.tf/profiles/76561198119149660#!/compare/1546560000/1546646400

https://backpack.tf/profiles/76561198119577562#!/compare/1546560000/1546646400

Sold for Blizzardy Storm Le Party Phantom ( 33.5 keys ) + Showstopper Taunt:The Victory Lap ( seller at 18 keys ) + 1 key pure ~ 53 keys

Seems like a quicksale as well, despite the low price and that it sold the same day as it was bought

Sale 9: https://backpack.tf/profiles/76561198056080374#!/compare/1546819200/1546905600

https://backpack.tf/profiles/76561198201364639#!/compare/1546819200/1546905600

https://backpack.tf/item/5758729115 - Deleted key on Bucks side which shows 59 keys instead of 58.

Sold for 58 keys pure.

Sale 10: https://backpack.tf/profiles/76561198051511947#!/compare/1547337600/1547510400

https://backpack.tf/profiles/76561198107260155#!/compare/1547424000/1547510400

Quicksold for 50.

Sales: 79, 69, 69, 67, 68 and 58. Going with a range of 60-80.