Sale 1:

https://backpack.tf/profiles/76561198021221797#!/compare/1550793600/1551312000

https://backpack.tf/profiles/76561198351665200#!/compare/1551225600/1551312000

Sold for 14 keys

Sale 2:

https://backpack.tf/profiles/76561198351665200#!/compare/1552262400/1552348800

https://backpack.tf/profiles/76561198126868898#!/compare/1526860800/1555027200

Sold for 15 keys

Sale 3:

https://backpack.tf/profiles/76561198841365001#!/compare/1549324800/1549411200

https://backpack.tf/profiles/76561198323565601#!/compare/1549411200/1549497600

Untrace

Sale 4:

https://backpack.tf/profiles/76561198161977280#!/compare/1549756800/1549843200

https://backpack.tf/profiles/76561198323565601#!/compare/1549756800/1549843200

QS for ~9 keys

Sale 5:

https://backpack.tf/profiles/76561198323565601#!/compare/1549843200/1549929600

https://backpack.tf/profiles/76561198089253101#!/compare/1549843200/1549929600

Tradeback between owner

Sale 6:

https://backpack.tf/profiles/76561198323565601#!/compare/1550016000/1550102400

https://backpack.tf/profiles/76561198396638749#!/compare/1550016000/1550102400

Sold for Slumber Bandito + ~1 key in sweets

Bandito Mini:

https://backpack.tf/suggestion/5ccbddce67807248877d41d6

Suggestion for 13.5 keys

Total is 14 .5 keys

https://bot.tf/stats/listings/4OL6QJQ4

B/O of 13 keys, capping

Sale 7:

https://backpack.tf/profiles/76561198396638749#!/compare/1550188800/1550275200

https://backpack.tf/profiles/76561198045607732#!/compare/1550188800/1550275200

Sold for CTFL Mirror

Use there

https://bot.tf/stats/listings/Y9XX9WNM

B/O of 14 keys

Sale 8:

https://backpack.tf/profiles/76561198045607732#!/compare/1550188800/1550275200

https://backpack.tf/profiles/76561198196861586#!/compare/1548892800/1550275200

Untrace, Keys?

Sale 9:

https://backpack.tf/profiles/76561198363395191#!/compare/1549670400/1549756800

https://backpack.tf/profiles/76561198204332904#!/compare/1549670400/1549756800

Sold for 14 keys(traceable as keys were used to buy Boron Beanie)

Sale 10:

https://backpack.tf/profiles/76561198204332904#!/compare/1552176000/1552262400

https://backpack.tf/profiles/76561198828803448#!/compare/1551312000/1552262400

Untrace

Sale 11:

https://backpack.tf/profiles/76561198277409359#!/compare/1552348800/1552435200

https://backpack.tf/profiles/76561198439167149#!/compare/1552176000/1552435200

Untrace

Sale 12:

https://backpack.tf/profiles/76561198277409359#!/compare/1552694400/1552780800

https://backpack.tf/profiles/76561198379996789#!/compare/1552694400/1552780800

Sold for ~15 keys

Sale 13:

https://backpack.tf/profiles/76561198379996789#!/compare/1553212800/1553299200

https://backpack.tf/profiles/76561198115074140#!/compare/1553212800/1553299200

Keys?

Sale 14:

https://backpack.tf/profiles/76561198115074140#!/compare/1553212800/1553299200

https://backpack.tf/profiles/76561198165205268#!/compare/1553212800/1553299200

Sold for 12 keys

Sale 15:

https://backpack.tf/profiles/76561198165205268#!/compare/1553472000/1553558400

https://backpack.tf/profiles/76561198046921199#!/compare/1553472000/1553558400

Keys....

Sale 16:

https://backpack.tf/profiles/76561198046921199#!/compare/1553558400/1553644800

https://backpack.tf/profiles/76561198343885717#!/compare/1553558400/1553644800

Sold with 2 keys for CTFL Connoisseur

Use there

https://bot.tf/stats/listings/MVW83OV4

B/O of 15 keys

Sale 17:

https://backpack.tf/profiles/76561198343885717#!/compare/1553558400/1553644800

https://backpack.tf/profiles/76561198271273735#!/compare/1553644800/1553731200

https://backpack.tf/profiles/76561198036394691#!/compare/1553558400/1553644800

Untrace

Sale 18:

https://marketplace.tf/items/30930;5;u29

$26.00 / $1.81 = 14.36 keys

Total sales @:

12, 13, 14, 14, 14, 14.36, 15, 15 keys

Seller at 15 keys,

Buyers up to ~11 keys,

Gonna exclude 12, close to buyers.

Taking 13 - 15 keys.