Sale 1:

https://backpack.tf/profiles/76561198812543484#!/compare/1567900800/1567987200

https://backpack.tf/profiles/76561198145439384#!/compare/1567900800/1567987200

Bulk

sale 2:

https://backpack.tf/profiles/76561198311981931#!/compare/1568160000/1568246400

https://backpack.tf/profiles/76561198145439384#!/compare/1568160000/1568246400

Untrace

sale 3:

https://backpack.tf/profiles/76561198048851745#!/compare/1561939200/1562025600

https://backpack.tf/profiles/76561198208687079#!/compare/1561939200/1562025600

Sold for 8 keys

Sale 4:

https://backpack.tf/profiles/76561198208687079#!/compare/1562025600/1562112000

https://backpack.tf/profiles/76561198845319318#!/compare/1562025600/1562112000

Sold for Searing Elite

Elite Mini:

https://backpack.tf/suggestion/5d8055e46780725bb93e21cf

Suggestion for 10 keys

Sale 5:

https://backpack.tf/profiles/76561198139909316#!/compare/1565740800/1565827200

https://backpack.tf/profiles/76561198098111356#!/compare/1565740800/1565827200

Sold for Bubbling Fat Man

use there

Sale 6:

https://backpack.tf/profiles/76561198098111356#!/compare/1565827200/1565913600

https://backpack.tf/profiles/76561198366902925#!/compare/1565827200/1565913600

Sold for G fetti Fat Man

Fat Mini:

https://backpack.tf/suggestion/5d8057e06780725c7d5e0a64

Suggestion for 9 keys

Sale 7:

https://backpack.tf/profiles/76561198366902925#!/compare/1565913600/1566259200

https://backpack.tf/profiles/76561198977391819#!/compare/1564876800/1566172800

Untrace

Sale 8:

https://backpack.tf/profiles/76561198977391819#!/compare/1566172800/1566259200

https://backpack.tf/profiles/76561198203657571#!/compare/1566172800/1566259200

Low

Sale 9:

https://backpack.tf/profiles/76561198203657571#!/compare/1566172800/1566259200

https://backpack.tf/profiles/76561198323565601#!/compare/1566172800/1566259200

Sold for 6 keys(1 used to buy scatter)

Sale 10:

https://backpack.tf/profiles/76561198021055079#!/compare/1565827200/1565913600

https://backpack.tf/profiles/76561198447297136#!/compare/1565827200/1565913600

Sold for Miami Outdoorsman

Outdoorsman Mini:

https://backpack.tf/suggestion/5d80538fd3817204bb040194

Suggestion for 10.5 keys

Sale 11 - 15:

https://marketplace.tf/items/tf2/30040;5;u59

$16.49 / $1.83 = 9.01 keys

$16.49 / $1.84 = 8.96 keys <--- https://backpack.tf/item/1789319798 or other sale

$16.00 / $1.84 = 8.70 keys <-- ^

$17.9 / $1.80 = 9.94 keys

$13.79 / $1.82 = 7.58 keys

Total sales @:

6, 7.5, 8, 8.5, 9, 9, 9, 10, 10, 10.5 keys

Buyers up to ~5 keys,

gonna call 6 low,

taking 7.5 - 10.5 keys (See G Fetti Fat Man Field Cap, one of the minis, for clarification if you wonder why I am rounding to 0.5)