Sale 1:

https://backpack.tf/profiles/76561198335337587#!/compare/1566086400/1566259200

https://backpack.tf/profiles/76561198117320629#!/compare/1566172800/1566259200

Sold for CTFL Kiss King(14)

sale 2:

https://backpack.tf/profiles/76561198117320629#!/compare/1566172800/1566259200

https://backpack.tf/profiles/76561198079504588#!/compare/1566172800/1566259200

Sold for keys

Sale 3:

https://backpack.tf/profiles/76561198079504588#!/compare/1566259200/1566345600

https://backpack.tf/profiles/76561198154023527#!/compare/1566000000/1566345600

Bulk

Sale 4:

https://backpack.tf/profiles/76561198154023527#!/compare/1566777600/1566864000

https://backpack.tf/profiles/76561198382378862#!/compare/1566777600/1566864000

Sold for C9 HoC

https://bot.tf/stats/listings/MGZP2R23

B/O of 17 keys

Sale 5:

https://backpack.tf/profiles/76561198382378862#!/compare/1566864000/1566950400

https://backpack.tf/profiles/76561198211890761#!/compare/1566864000/1566950400

Sold for 14 Keys

Sale 6:

https://backpack.tf/profiles/76561198211890761#!/compare/1566950400/1567036800

https://backpack.tf/profiles/76561198802184359#!/compare/1567036800/1567123200

Sold for 14 keys

sale 7:

https://backpack.tf/profiles/76561198802184359#!/compare/1568073600/1568246400

https://backpack.tf/profiles/76561198047096883#!/compare/1568160000/1568246400

Sold for ~18 keys

Sale 8:

https://backpack.tf/profiles/76561198047096883#!/compare/1568851200/1568937600

https://backpack.tf/profiles/76561198877733644#!/compare/1568851200/1568937600

Sold for 14 keys

Sale 9:

https://backpack.tf/profiles/76561198877733644#!/compare/1568937600/1569024000

https://backpack.tf/profiles/76561198337734785#!/compare/1568937600/1569024000

Sold for ~13 keys

sale 10:

https://backpack.tf/profiles/76561198337734785#!/compare/1569456000/1569542400

https://backpack.tf/profiles/76561198195587114#!/compare/1569542400/1571184000

Sold for ~15 keys

sale 11:

https://backpack.tf/profiles/76561198195587114#!/compare/1572134400/1572220800

https://backpack.tf/profiles/76561198337734785#!/compare/1572048000/1572134400

Sold for ~13 keys (QS)

Sale 12:

https://backpack.tf/profiles/76561198354656940#!/compare/1567641600/1567728000

https://backpack.tf/profiles/76561198169756327#!/compare/1567641600/1567728000

Sold for ~14 keys

sale 13:

https://backpack.tf/profiles/76561198169756327#!/compare/1567728000/1567814400

https://backpack.tf/profiles/76561198089664680#!/compare/1567641600/1567814400

Sold for Stormy Merryweather(16)

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

B/O of 15 keys, capping

Sale 14:

https://backpack.tf/profiles/76561198089664680#!/compare/1567641600/1567814400

https://backpack.tf/profiles/76561198310264826#!/compare/1567728000/1567814400

Sold for Blizzardy Buddy + ~4 keys in sweets

Sale 15:

https://backpack.tf/profiles/76561198310264826#!/compare/1567814400/1567900800

https://backpack.tf/profiles/76561198121635128#!/compare/1567814400/1567900800

Sold with ~1 key in sweets for 13 keys

total is 12 keys

Sale 16:

https://backpack.tf/profiles/76561198121635128#!/compare/1567900800/1567987200

https://backpack.tf/profiles/76561198131799675#!/compare/1567900800/1567987200

Sold with ~1 key in sweets for Lantern Handle

https://bot.tf/stats/listings/Y3570X5R

B/O of 16 keys

sale 17:

https://backpack.tf/profiles/76561198131799675#!/compare/1567900800/1567987200

https://backpack.tf/profiles/76561198337734785#!/compare/1567900800/1567987200

QS

Sale 18:

https://backpack.tf/profiles/76561198337734785#!/compare/1567987200/1568073600

https://backpack.tf/profiles/76561198417437790#!/compare/1567900800/1568419200

Keys

sale 19 - 21:

https://marketplace.tf/items/tf2/55;5;u36

$22.53 / $1.83 = 12.31 keys

$29.29 / $1.83 = 16.01 keys

$25 / $1.82 = 13.74 keys

Total sales @:

12, 12, 13, 13, 14, 14, 14, 14, 14, 14, 15, 15, 16, 18 keys

gonna say i have enough sales to call the rest 'use there',

buyers up to 13 keys,

seller at 15 keys,

let's go with 14 - 15 keys.