Sale 1:

https://backpack.tf/profiles/76561198142717084#!/compare/1548028800/1548288000

https://backpack.tf/profiles/76561198011321852#!/compare/1547942400/1548028800

Sold for Aces Samur-Eye(15)

Sale 2:

https://backpack.tf/profiles/76561197994036615#!/compare/1547942400/1548979200

https://backpack.tf/profiles/76561198036641147#!/compare/1547683200/1547942400

Untrace

Sale 3:

https://backpack.tf/profiles/76561198036641147#!/compare/1548720000/1548806400

https://backpack.tf/profiles/76561198868855109#!/compare/1548720000/1548806400

Sold for 12 Keys (used to buy P Fetti Bonk)

Sale 4:

https://backpack.tf/profiles/76561198868855109#!/compare/1548892800/1548979200

https://backpack.tf/profiles/76561198273675032#!/compare/1548892800/1548979200

Bulky

Sale 5:

https://backpack.tf/profiles/76561198273675032#!/compare/1548979200/1549065600

https://backpack.tf/profiles/76561198261300011#!/compare/1549065600/1549152000

Untrace

Sale 6:

https://backpack.tf/profiles/76561198261300011#!/compare/1549065600/1549152000

https://backpack.tf/profiles/76561198384337664#!/compare/1548460800/1549152000

Sold for Bubbling Chieftain + 4 keys

Use there

Sale 7:

https://backpack.tf/profiles/76561198322571758#!/compare/1552262400/1552435200

https://backpack.tf/profiles/76561198165055074#!/compare/1552176000/1552262400

Bulk

Sale 8:

https://backpack.tf/profiles/76561198076417722#!/compare/1547596800/1547769600

https://backpack.tf/profiles/76561198337734785#!/compare/1547510400/1547596800

QS?

Sale 9:

https://backpack.tf/profiles/76561198337734785#!/compare/1547769600/1547856000

https://backpack.tf/profiles/76561198101398885#!/compare/1547769600/1547856000

Keys

Sale 10:

https://backpack.tf/profiles/76561198101398885#!/compare/1548460800/1548633600

https://backpack.tf/profiles/76561198108988160#!/compare/1548547200/1548633600

Sold for DBD Sterling(17)

Sale 11:

https://backpack.tf/profiles/76561198108988160#!/compare/1548547200/1548633600

https://backpack.tf/profiles/76561198269401214#!/compare/1548547200/1548633600

Sold for 13 keys

Sale 12:

https://backpack.tf/profiles/76561198269401214#!/compare/1548547200/1548633600

https://backpack.tf/profiles/76561198269401214#!/compare/1548547200/1548633600

Bulk

Sale 13:

https://backpack.tf/profiles/76561198269636307#!/compare/1548460800/1548633600

https://backpack.tf/profiles/76561198829227614#!/compare/1548547200/1548633600

Sold for negligible sweets for KaW Dogger

Use there

Sale 14:

https://backpack.tf/profiles/76561198138889611#!/compare/1549584000/1549756800

https://backpack.tf/profiles/76561198349181069#!/compare/1549670400/1549756800

Sold for ~12 keys

Sale 15:

https://backpack.tf/profiles/76561198349181069#!/compare/1549670400/1549756800

https://backpack.tf/profiles/76561198261300011#!/compare/1549756800/1549843200

Can't accurately trace

Sale 16:

https://backpack.tf/profiles/76561198261300011#!/compare/1553472000/1553558400

https://backpack.tf/profiles/76561198036394691#!/compare/1553472000/1553558400

Sold for TW Tippler + 2 keys

Use there

Sale 17:

https://backpack.tf/profiles/76561198036394691#!/compare/1553558400/1553644800

https://backpack.tf/profiles/76561198930460537#!/compare/1553558400/1553644800

Sold with 1 key for N&B Runner

Use there

Sale 18:

https://backpack.tf/profiles/76561198930460537#!/compare/1553558400/1553644800

https://backpack.tf/profiles/76561198866486021#!/compare/1553558400/1553644800

Sold for Bubbling Sky High(10) + 6 keys

Total is 17 keys

Sale 19:

https://marketplace.tf/items/30863;5;u35

$29.79 / $1.78 = 16.74 keys

Total sales @:

12, 12, 13, 15, 16.74, 17, 17 keys

Buyers up to 11 keys,

Sellers down to 14 keys,

unsolds at 16 keys,

Gonna take 12 - 15 keys