Taking from this suggestion: https://backpack.tf/suggestion/5e081af8a3ed152bc8484ee1

This is originally not my suggestion, all credits to the original suggester and those who put effort into this.

//

Provided by ❆SubZeroDestruction❆

Sale 1:

https://backpack.tf/item/7453590514

https://backpack.tf/profiles/76561198031524068#!/compare/1572480000/1572652800

https://backpack.tf/profiles/76561198050617344#!/compare/1564444800/1573171200

Untraceable

Sale 2:

https://backpack.tf/item/7246914359

https://backpack.tf/profiles/76561198240841312#!/compare/1570320000/1572134400

https://backpack.tf/profiles/76561198084089059#!/compare/1568160000/1573776000

Untraceable

Sale 3:

https://backpack.tf/item/7463333729

https://backpack.tf/profiles/76561198080394134#!/compare/1572393600/1572480000

https://backpack.tf/profiles/76561198064873366#!/compare/1572134400/1572652800

Untraceable

Sale 4:

https://backpack.tf/item/5558641246

https://backpack.tf/profiles/76561198868286835#!/compare/1571702400/1571875200

https://backpack.tf/profiles/76561198197215790#!/compare/1571702400/1571961600

Untraceable

Sale 5:

https://backpack.tf/item/6449103907

Sold for 10 Keys Pure

https://backpack.tf/profiles/76561198278481498#!/compare/1571011200/1571184000

https://backpack.tf/profiles/76561198260201158#!/compare/1571011200/1571097600

Sale 6:

https://backpack.tf/item/6449103907

https://backpack.tf/profiles/76561198328984748#!/compare/1570752000/1570924800

https://backpack.tf/profiles/76561198278481498#!/compare/1570752000/1571011200

Untraceable

Sale 7:

https://backpack.tf/item/6803308422

Sold for 14 Keys Pure

https://backpack.tf/profiles/76561198093788180#!/compare/1571443200/1571616000

https://backpack.tf/profiles/76561198119198857#!/compare/1571443200/1571616000

Sale 8:

https://backpack.tf/item/6396436557

https://backpack.tf/profiles/76561198424722948#!/compare/1576108800/1576368000

https://backpack.tf/profiles/76561198072073083#!/compare/1574812800/1576281600

Untraceable

Sale 9:

https://backpack.tf/item/6396436557

https://backpack.tf/profiles/76561198101092551#!/compare/1575849600/1575936000

https://backpack.tf/profiles/76561198424722948#!/compare/1575849600/1575936000

Untraceable

Sale 10:

https://backpack.tf/item/6122004665

Sold with 2 Keys for a Steaming Tartan Spartan (8.5 Keys)

Going with 6.5 Keys

https://backpack.tf/profiles/76561198431364010#!/compare/1575676800/1575763200

https://backpack.tf/profiles/76561198118518523#!/compare/1575676800/1575763200

Marketplace Sales:

https://marketplace.tf/items/tf2/30816;5;u3030

Sale 11:

https://backpack.tf/item/7931452281

Sold on Oct 14th for $30, Keys were $1.82

Rounding 16.48~ Keys down to 16 Keys

Sale 12:

https://backpack.tf/item/5837960826

Sold on Nov 28th for $17.79, Keys were $1.73

Rounding 10.28~ keys down to 10 Keys

///

Provided by Shuffle Spy:

https://backpack.tf/profiles/76561198049312442#!/compare/1579132800/1579392000 - 8 Keys

https://backpack.tf/profiles/76561198928421771#!/compare/1578614400/1578700800 - 9 Keys

https://backpack.tf/profiles/76561198065176679#!/compare/1579824000/1579910400 - Bulk

https://backpack.tf/profiles/76561198010332638#!/compare/1578960000/1579046400 - Better for the Elf

https://backpack.tf/profiles/76561198856052541#!/compare/1578960000/1579046400 - Can drop the Vivid Elf

https://backpack.tf/profiles/76561198856052541#!/compare/1580169600/1580256000 - 4 Keys to a buy order

https://backpack.tf/profiles/76561198279670065#!/compare/1581120000/1581206400 - Static Mist Skullcracker (6.25 Keys)

https://marketplace.tf/items/tf2/30816;5;u3030 - Sold for $15 when Keys were ~$1.78 each (8.5 Keys) and $13.5 when Keys were ~$1.75 each (7.5 Keys)

https://imgur.com/a/hygQyfh - 4 Day Seller at 5 Keys and a 1 Month Seller at 6 Keys

https://backpack.tf/u/76561198311981931

https://backpack.tf/u/76561198125791160

As per moderator suggestion, taking a range of 5-6.5 keys

https://backpack.tf/suggestion/5e081af8a3ed152bc8484ee1