Sale 1:

https://backpack.tf/profiles/76561198122387677#!/compare/1592006400/1592611200

https://backpack.tf/profiles/76561198436888610#!/compare/1592092800/1593302400

Untrace

sale 2:

https://backpack.tf/profiles/76561198983415577#!/compare/1590624000/1590796800

https://backpack.tf/profiles/76561198101083663#!/compare/1590624000/1590710400

Untrace

sale 3:

https://backpack.tf/profiles/76561198101083663#!/compare/1590624000/1590710400

https://backpack.tf/profiles/76561198283413510#!/compare/1589328000/1590710400

Sold with negligible sweets for DP HWAH

https://bot.tf/stats/listings/MNRWN62Q

B/O of 5 keys, caps easily by buyers.

sale 4:

https://backpack.tf/profiles/76561198283413510#!/compare/1590710400/1594684800

https://backpack.tf/profiles/76561198280693486#!/compare/1590710400/1590796800

Qs

sale 5:

https://backpack.tf/profiles/76561198280693486#!/compare/1590796800/1590883200

https://backpack.tf/profiles/76561198343426789#!/compare/1590624000/1590883200

Sold for ~4.05 keys

sale 6:

https://backpack.tf/profiles/76561198343426789#!/compare/1592092800/1592265600

https://backpack.tf/profiles/76561198087728099#!/compare/1592006400/1594425600

Sold for ~4.54 keys (2 keys + 24 ref used to buy Grail Punch)

sale 7:

https://marketplace.tf/items/tf2/1113;5;u3026

$10.99 / $2.03 = 5.41 keys

$8.95 / $1.98 = 4.52 keys

$9 / $1.99 = 4.52 keys

Total sales @:

4.05, 4.5, 4.5, 4.55, 5, 5.4 keys

buyers up to 3.39 keys,

given that 5 is capped from much higher (minimum 6),

and QS within a day,

let's call 5.4 high,

4.05 low to balance,

taking 4.5 - 5 keys.