Sale 1:

https://backpack.tf/profiles/76561198370756100#!/compare/1584576000/1584662400

https://backpack.tf/profiles/76561198212556179#!/compare/1584489600/1584662400

https://backpack.tf/profiles/76561198370756100#!/compare/1584576000/1584662400

tradeback

sale 2:

https://backpack.tf/profiles/76561198118157202#!/compare/1584835200/1584921600

https://backpack.tf/profiles/76561198878948902#!/compare/1584835200/1584921600

Untrace

sale 3:

https://backpack.tf/profiles/76561198878948902#!/compare/1584921600/1585094400

https://backpack.tf/profiles/76561198850274253#!/compare/1584835200/1584921600

QS

sale 4:

https://backpack.tf/profiles/76561198305494036#!/compare/1590019200/1590105600

https://backpack.tf/profiles/76561198802991149#!/compare/1590364800/1590537600

https://backpack.tf/profiles/76561198137524012#!/compare/1590451200/1590537600

https://backpack.tf/profiles/76561198880361166#!/compare/1590537600/1590624000

Untrace / Bulk

sale 5:

https://backpack.tf/profiles/76561198880361166#!/compare/1590796800/1590883200

https://backpack.tf/profiles/76561199013070847#!/compare/1591142400/1591228800

https://backpack.tf/profiles/76561199013070847#!/compare/1591142400/1591228800

Untrace / QS

sale 6:

https://backpack.tf/profiles/76561198305494036#!/compare/1591315200/1591401600

https://backpack.tf/profiles/76561198203564124#!/compare/1591401600/1591488000

Sold for 18 keys

Sale 7:

https://backpack.tf/profiles/76561198203564124#!/compare/1591401600/1591488000

https://backpack.tf/profiles/76561198386346780#!/compare/1591401600/1591488000

Sold for G fetti Nickel + 5 keys

Nickel Mini:

https://backpack.tf/suggestion/5eebdb6842fa475adb1ac17a

Suggestion for 12 keys

Total is 17 keys

Sale 8:

https://backpack.tf/profiles/76561198386346780#!/compare/1591401600/1591488000

https://backpack.tf/profiles/76561198146784656#!/compare/1591315200/1591488000

Sold with 5 keys for 5D Backbreaker

use there

Sale 9:

https://backpack.tf/profiles/76561198146784656#!/compare/1591315200/1591488000

https://backpack.tf/profiles/76561198413058872#!/compare/1591401600/1591488000

Sold for Stormy Greased + ~2 keys in sweets

greased Mini:

https://backpack.tf/suggestion/5eebe83a5409db78b96e2552

Suggestion for 17.5 keys

Total is 19.5 keys

sale 10:

https://backpack.tf/profiles/76561198413058872#!/compare/1591574400/1591488000

https://backpack.tf/profiles/76561199025327447#!/compare/1591574400/1591574400

https://backpack.tf/profiles/76561198413058872#!/compare/1591488000/1591574400

Transfer

sale 11:

https://backpack.tf/profiles/76561198413058872#!/compare/1591574400/1591660800

https://backpack.tf/profiles/76561198077730629#!/compare/1591574400/1591660800

Bulk

sale 12:

https://backpack.tf/profiles/76561198077730629#!/compare/1592092800/1592265600

https://backpack.tf/profiles/76561198153874080#!/compare/1592265600/1592352000

Transfer

Sale 13:

https://backpack.tf/profiles/76561198114903061#!/compare/1591574400/1591920000

https://backpack.tf/profiles/76561198396499936#!/compare/1591833600/1591920000

Bulk

sale 14:

https://marketplace.tf/items/tf2/1093;5;u58

$38 / $1.97 = 19.29 keys

Total sales @:

17, 18, 19, 20 keys

buyers up to 16 keys,

considering 18 resold for lower,

taking 17 - 20 keys.