Sale 1:

https://marketplace.tf/items/tf2/30623;5;u17

https://backpack.tf/item/7735876173

$99 / $1.73 = 57.23 keys

under buyers: https://imgur.com/a/lFUSoob

Sale 2:

mp sale

https://backpack.tf/profiles/76561198043936328#!/compare/1574640000/1574726400

Sale 3:

bulk for cat hat

https://backpack.tf/profiles/76561198110477461#!/compare/1570406400/1570665600

https://backpack.tf/profiles/76561198160856661#!/compare/1570579200/1570665600

Sale 4:

bulk

https://backpack.tf/profiles/76561198139171368#!/compare/1568073600/1570665600

https://backpack.tf/profiles/76561198160856661#!/compare/1570579200/1570665600

Sale 5:

72 keys

69 keys + buds(3 keys)

https://backpack.tf/profiles/76561198139171368#!/compare/1574208000/1574294400

https://backpack.tf/profiles/76561198055552635#!/compare/1574208000/1574294400

Sale 6:

Misty Skull Flipped Trilby(87 keys)

https://backpack.tf/profiles/76561198055552635#!/compare/1575072000/1575244800

https://backpack.tf/profiles/76561198059021831#!/compare/1575158400/1575244800

Flipped Trilby: https://backpack.tf/suggestion/5df2f9e46353fc35731b8fa5

Sale 7:

104 keys

https://backpack.tf/profiles/76561198059021831#!/compare/1575590400/1575676800

https://backpack.tf/profiles/76561198137138415#!/compare/1574899200/1575676800

Sale 8:

bulk

https://backpack.tf/profiles/76561198016250523#!/compare/1571356800/1571529600

https://backpack.tf/profiles/76561198050745352#!/compare/1571443200/1571529600

Sale 9:

176

no b/o found

stormy rack(77.5) + Pro KS Aussie RL(48) + Dark Doorway Vanquisher(50)

https://backpack.tf/profiles/76561198023635911#!/compare/1573516800/1573603200

https://backpack.tf/profiles/76561198050745352#!/compare/1573516800/1573603200

Vanquisher: https://backpack.tf/suggestion/5df675b9112ca84d636dead9

Rack: https://backpack.tf/suggestion/5df67dfbf9326e473d6ae6b5

RL: https://imgur.com/a/U8xHKsa

Sale 10:

bulkish for keys

https://backpack.tf/profiles/76561198023635911#!/compare/1573948800/1574121600

https://backpack.tf/profiles/76561198117390056#!/compare/1574035200/1574121600

Sale 11:

bulk for noh mercy

https://backpack.tf/profiles/76561198072164101#!/compare/1574121600/1574208000

https://backpack.tf/profiles/76561198117390056#!/compare/1574121600/1574208000

Sale 12:

no mini for Frontier Djustice: https://backpack.tf/suggestion/5df2d3d265b6c474de017eff

https://backpack.tf/profiles/76561198072164101#!/compare/1574467200/1574553600

https://backpack.tf/profiles/76561198293654690#!/compare/1574467200/1574553600

Sale 13:

95 pure

https://backpack.tf/profiles/76561198119225304#!/compare/1568764800/1569024000

https://backpack.tf/profiles/76561198858693419#!/compare/1568937600/1569024000

Sale 14:

Vivid Plasma Tough Stuff Muffs

looking at a few sales on muffs would definitely be under buyers: https://imgur.com/a/mGgjjF8

https://backpack.tf/profiles/76561198858693419#!/compare/1569369600/1569456000

https://backpack.tf/profiles/76561197994697258#!/compare/1569369600/1569456000

Sale 15:

89 keys

MG Titanium Tyrolean(36.5) + C9 Baker Boy(19.5) + Pfetti Gauzed Gaze(22) + 11 keys

https://backpack.tf/profiles/76561197994697258#!/compare/1570320000/1570406400

https://backpack.tf/profiles/76561198223331996#!/compare/1570320000/1570406400

Tyrolean: https://backpack.tf/suggestion/5df2e288db517f3065762198

Sale 16:

untrace

https://backpack.tf/profiles/76561198223331996#!/compare/1572566400/1572652800

https://backpack.tf/profiles/76561198998797764#!/compare/1573171200/1573257600

==============================================================================

Sales:

57,72,87,89,95,104,176

57 under buyers

176 clear outlier