https://steamcommunity.com/market/listings/440/Strange%20Collector%27s%20Professional%20Killstreak%20Phlogistinator

August 18 - $100.81 = Quicksell price

August 26 - $169.61 = 72 keys

August 29 - $172.49 = 73 keys

October 20 - $192.99 = 83 keys

https://marketplace.tf/items/tf2/594;14;strange

$89.99, quickbuyers above this price

https://marketplace.tf/items/tf2/594;14;strange;kt-3

$350, this one was double spelled, excluding https://backpack.tf/item/3018761949

https://backpack.tf/item/2852328611

this one was double spelled, excluding this also

https://backpack.tf/profiles/76561198009309781#!/compare/1571529600/1571702400

https://backpack.tf/profiles/76561198312480435#!/compare/1571616000/1571702400

Quicksell for 52 keys

https://backpack.tf/profiles/76561198905234101#!/compare/1568073600/1569888000

https://backpack.tf/profiles/76561198026194410#!/compare/1569715200/1569801600

100 keys

https://backpack.tf/profiles/76561198056753179#!/compare/1567036800/1567123200

https://backpack.tf/profiles/76561198026194410#!/compare/1567036800/1567123200

60 keys, which is the one that eventually sold for 100 keys

https://backpack.tf/profiles/76561198370509151#!/compare/1568592000/1569283200

https://backpack.tf/profiles/76561198987544944#!/compare/1569283200/1569628800

bulk or account transfer

https://backpack.tf/profiles/76561198370509151#!/compare/1567209600/1567296000

https://backpack.tf/profiles/76561198168863803#!/compare/1567209600/1567296000

Upgrade for double spelled, not using

https://backpack.tf/profiles/76561198026194410#!/compare/1569974400/1570060800

https://backpack.tf/profiles/76561198342136112#!/compare/1569974400/1570060800

35 keys? yikes

https://backpack.tf/profiles/76561198168863803#!/compare/1568332800/1568419200

https://backpack.tf/profiles/76561198146627532#!/compare/1568332800/1568419200

100 keys, no keys were exchanged with the chiro frenchman's / frostbite head warmer

https://backpack.tf/profiles/76561198086247757#!/compare/1568419200/1568505600

Sales:

35

52

60

72

73

83

100

100

Sellers:

https://backpack.tf/classifieds?item=Phlogistinator&quality=14&tradable=1&craftable=1&australium=-1

Two for 100 keys

https://marketplace.tf/items/tf2/594;14;strange;kt-3

$250.00 = ~139 keys

https://steamcommunity.com/market/listings/440/Strange%20Collector%27s%20Professional%20Killstreak%20Phlogistinator

Three for ~84-100 keys

Buyers at 50-54 keys

Going with 70-100 keys.

https://marketplace.tf/items/tf2/594;14;strange

I bought it for $90.00, which is under quickbuyers at ~50 keys