Resuggestion, thanks to Blaze & Shuffle for the info!

Sale 1:

https://backpack.tf/profiles/76561198263476165#!/compare/1545004800/1545091200

https://backpack.tf/profiles/76561198796233706#!/compare/1542412800/1542499200

Untrace

Sale 2:

https://backpack.tf/profiles/76561198796233706#!/compare/1542499200/1542672000

https://backpack.tf/profiles/76561198369202740#!/compare/1542585600/1542672000

Sold for 12 keys

Sale 3:

https://backpack.tf/profiles/76561198369202740#!/compare/1542672000/1543017600

https://backpack.tf/profiles/76561198182213262#!/compare/1543017600/1543104000

Sold for 11 keys

Sale 4:

https://backpack.tf/profiles/76561198182213262#!/compare/1545004800/1545091200

https://backpack.tf/profiles/76561198263476165#!/compare/1545004800/1545091200

Sold for P Fetti Base Metal + 4 keys + 0.5 keys in spelled items

Spelled Mini:

https://backpack.tf/profiles/76561198806861785#!/compare/1541376000/1541462400

Sold for 0.5 keys in sweets

Metal Mini:

https://backpack.tf/suggestion/5c441b61cf6c75278c12ca6f

Suggestion for 11 keys

Total is 15.5 keys

Sale 5:

https://backpack.tf/profiles/76561198263476165#!/compare/1545177600/1545264000

https://backpack.tf/profiles/76561198050859478#!/compare/1545264000/1545350400

Sold for DBD Puffy Cap

Puffy Mini:

https://backpack.tf/suggestion/5c4417f144325a6ff506c219

Suggestion for 16 keys

Sale 6:

https://backpack.tf/profiles/76561198050859478#!/compare/1545264000/1545350400

https://backpack.tf/profiles/76561198157089186#!/compare/1545350400/1545436800

10 keys?

Sale 7:

https://backpack.tf/profiles/76561198157089186#!/compare/1545436800/1545782400

https://backpack.tf/profiles/76561198097381339#!/compare/1545609600/1545696000

Sold for 11 keys

Sale 8:

https://backpack.tf/profiles/76561198097381339#!/compare/1545868800/1545955200

https://backpack.tf/profiles/76561198072898758#!/compare/1545868800/1545955200

https://backpack.tf/profiles/76561198129334953#!/compare/1545004800/1545955200

Untrace

Total sales @:

11, 11, 12, 15.5, 16 keys

Shuffle's Part:

Sale 8's not Untraceable - it sold for the Slo-Poke.

If you're concerned other items were involved, you can ask the Seller/Buyer, but the Slo-Poke 100% matches.

As for a Mini on that, was gonna price that Slo-Poke with this, so here's the other Slo-Poke sale:

https://backpack.tf/profiles/76561198097381339#!/compare/1546128000/1546214400 - Circling TF Logo Engineer's Cap (15.5 Keys)

https://backpack.tf/suggestion/5c48a41e44325a726b30b9dd - 15.5 Keys, rounds to 16 Keys

Blaze's Part:

There are as many sales around 11-12 as there are around 16 (even one more if we take sale 6 in account), so this will need a range.

Either 11-16 or 12-16 will work here. The first option includes all sales and the second excludes 11 due to current classies buyer at that. Not a big difference, so up to you.

Gonna go with 11 - 16, one buyer shouldn't counter multiple sales.