Sale 1:

https://backpack.tf/profiles/76561198024867201#!/compare/1541808000/1541894400

https://backpack.tf/profiles/76561198152430058#!/compare/1503619200/1545177600

Untrace

Sale 2:

https://backpack.tf/profiles/76561198363395191#!/compare/1539907200/1539993600

https://backpack.tf/profiles/76561198171133082#!/compare/1539907200/1540252800

Sold for 14 keys

Sale 3:

https://backpack.tf/profiles/76561198171133082#!/compare/1542412800/1547856000

https://backpack.tf/profiles/76561198129467214#!/compare/1544054400/1544400000

https://backpack.tf/profiles/76561198043936328#!/compare/1544400000/1544486400

https://backpack.tf/profiles/76561198085705161#!/compare/1544486400/1544659200

Untrace

Sale 4:

https://backpack.tf/profiles/76561198010742559#!/compare/1541808000/1541894400

https://backpack.tf/profiles/76561198050414618#!/compare/1541808000/1541894400

Sold for 12 keys

Sale 5:

https://backpack.tf/profiles/76561198050414618#!/compare/1541980800/1542067200

https://backpack.tf/profiles/76561198342161127#!/compare/1541980800/1542067200

Untrace

Sale 6:

https://backpack.tf/profiles/76561198156255538#!/compare/1547164800/1547251200

https://backpack.tf/profiles/76561198124887048#!/compare/1547164800/1547251200

Sold for Bubbling Bucket + 4 keys

Use there

Sale 7:

https://backpack.tf/profiles/76561198055221867#!/compare/1546387200/1546646400

https://backpack.tf/profiles/76561198002757046#!/compare/1546300800/1546387200

https://backpack.tf/profiles/76561198036907469#!/compare/1546387200/1546473600

https://backpack.tf/profiles/76561198090153676#!/compare/1546300800/1546387200

Untrace

Sale 8:

https://backpack.tf/profiles/76561198090153676#!/compare/1546473600/1546560000

https://backpack.tf/profiles/76561198098549418#!/compare/1546387200/1546560000

Untrace

Sale 9:

https://backpack.tf/profiles/76561198098549418#!/compare/1546560000/1546646400

https://backpack.tf/profiles/76561198205629231#!/compare/1546560000/1546646400

Sold for 15 keys

Sale 10:

https://backpack.tf/profiles/76561198321327719#!/compare/1541548800/1541721600

https://backpack.tf/profiles/76561198169467082#!/compare/1541721600/1541808000

Sold with ~2 keys in sweets for a Aussie GL(15)

Total is 13 keys

Sale 11:

https://backpack.tf/profiles/76561198169467082#!/compare/1542585600/1542672000

https://backpack.tf/profiles/76561198318209799#!/compare/1542672000/1542758400

Sold for 14 keys

Sale 12:

https://backpack.tf/profiles/76561198318209799#!/compare/1542844800/1542931200

https://backpack.tf/profiles/76561198179928535#!/compare/1542844800/1542931200

Used there

Sale 13:

https://backpack.tf/profiles/76561198179928535#!/compare/1542844800/1542931200

https://backpack.tf/profiles/76561198350879574#!/compare/1542844800/1542931200

Keys, or Brain Bowl, can't tell

Sale 14:

https://backpack.tf/profiles/76561198350879574#!/compare/1543190400/1543363200

https://backpack.tf/profiles/76561198310171759#!/compare/1543276800/1543363200

Sold for Bubbling Rouser(16) with ~1 key in sweets

Total is 17 keys

Sale 15:

https://backpack.tf/profiles/76561198310171759#!/compare/1543622400/1543708800

https://backpack.tf/profiles/76561198074879249#!/compare/1543708800/1543795200

Sold for Aces Nickel(13)

Sale 16:

https://backpack.tf/profiles/76561198074879249#!/compare/1544227200/1544400000

https://backpack.tf/profiles/76561198050414618#!/compare/1544313600/1544400000

Sold for keys

Sale 17:

https://backpack.tf/profiles/76561198259500466#!/compare/1544572800/1544659200

https://backpack.tf/profiles/76561198070652981#!/compare/1544572800/1544659200

Sold for C9 Katyusha + 3 keys

Use there

Sale 18:

https://backpack.tf/profiles/76561198070652981#!/compare/1544659200/1544745600

https://backpack.tf/profiles/76561198085363794#!/compare/1544572800/1544659200

Untrace

Sale 19:

https://backpack.tf/profiles/76561198085363794#!/compare/1544572800/1544659200

https://backpack.tf/profiles/76561198316708254#!/compare/1544400000/1544659200

Sold for 14 keys

Sale 20:

https://backpack.tf/profiles/76561198316708254#!/compare/1544745600/1544832000

https://backpack.tf/profiles/76561198101770271#!/compare/1544745600/1544832000

Sold for 15 keys

Sale 21:

https://backpack.tf/profiles/76561198101770271#!/compare/1544745600/1544832000

https://backpack.tf/profiles/76561198375567546#!/compare/1544745600/1544832000

Sold with ~3 keys in sweets for Stormy Front Runner

Use there

Sale 22:

https://backpack.tf/profiles/76561198873654564#!/compare/1545004800/1545091200

https://backpack.tf/profiles/76561198304343915#!/compare/1545004800/1545091200

Scammer

Sale 23:

https://backpack.tf/profiles/76561198304343915#!/compare/1545091200/1545177600

https://backpack.tf/profiles/76561198267750483#!/compare/1545091200/1545177600

Sold for ~11 keys

Sale 24:

https://backpack.tf/profiles/76561198267750483#!/compare/1545177600/1545264000

https://backpack.tf/profiles/76561198050859478#!/compare/1545177600/1545264000

Sold for DBD Airdog

Use there.

Sale 25:

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

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

Sold for G Fetti Chief

Use there

Sale 26:

https://backpack.tf/profiles/76561198263476165#!/compare/1545609600/1545782400

https://backpack.tf/profiles/76561198254620348#!/compare/1545696000/1545782400

Sold with ~7 keys in sweets for HG Baker(25.5)

Total is 18.5 keys

Sale 27:

https://backpack.tf/profiles/76561198254620348#!/compare/1545782400/1545868800

https://backpack.tf/profiles/76561198142724783#!/compare/1545523200/1545868800

Sold for 13 keys

Sale 28:

https://backpack.tf/profiles/76561198142724783#!/compare/1545868800/1545955200

https://backpack.tf/profiles/76561198836704562#!/compare/1545782400/1545868800

Can only trace 9 keys

Sale 29:

https://marketplace.tf/items/30958;5;u62

3 sales below buyers,

One sale for 28.99 USD,

Keys at 1.64 USD

Total is 17.68 keys

Total sales @:

11, 12, 13, 13, 13, 14, 14, 14, 15, 15, 17, 17.68, 18.5 keys

Gonna say all unusual sales use there, enough pure sales across the board to cover it.

Buyers up to 12 keys,

Very new seller for 17, watching.

https://backpack.tf/item/6459552008

Taking 13 - 19 keys.