Credits to: Zenith, soda - and Crummy's Burgers for providing screenshots

Sale 1:

Sold for 52 keys+a key in items:

https://backpack.tf/profiles/76561198095697847#!/compare/1607731200/1607817600

https://backpack.tf/profiles/76561198197324337#!/compare/1607817600/1607904000

Sale 2:

sold for a Cauldron Bubbles Dapper Topper(60)+4 keys:

https://prnt.sc/1011x3j

Sale 3:

Sold for 56 keys:

https://backpack.tf/profiles/76561198053720151#!/compare/1611014400/1611100800

https://backpack.tf/profiles/76561198335271745#!/compare/1611014400/1611100800

Sale 4:

Sold for 100 keys:

https://steamuserimages-a.akamaihd.net/ugc/1758063603367075514/B3BD1A9A9B49C2AE05B3D9634DDDA2BB30947E77/

Mini for Dapper:

Sale 1:

Sold for a Starstorm Slumber Toadstool

https://backpack.tf/profiles/76561198316717862#!/compare/1608422400/1608508800

https://backpack.tf/profiles/76561198162280204#!/compare/1608336000/1608508800

(the toadstool topper was dumped the same day so not counting)

Sale 2:

Sold for 60 keys

https://backpack.tf/profiles/76561198316717862#!/compare/1608508800/1608681600

https://backpack.tf/profiles/76561198035334988#!/compare/1608595200/1608681600

Sale 3:

Sold+4 keys for a HP.JR Gatsby

https://prnt.sc/1019srj

Sale 4:

Quicksold to a bot for 48 keys:

https://backpack.tf/profiles/76561198197324337#!/compare/1608768000/1608854400

Sale 5:

untrace:

https://backpack.tf/profiles/76561198337734785#!/compare/1609977600/1610064000

https://backpack.tf/profiles/76561198117433241#!/compare/1609977600/1610064000

Sale 6:

untrace, looks like a dump:

https://backpack.tf/profiles/76561198117433241#!/compare/1610496000/1610582400

https://backpack.tf/profiles/76561199101484822#!/compare/1610496000/1610582400

Only usable sale for Dapper is at 60

Calculation:

Sale 1 ~(53)

Sale 2 ~(64)

Sale 3 ~(56)

Sale 4 seems like an outlier so I'm not counting

going with 53-64