Minor adjustment to this suggestion.

Time for an update!

Strange Miami Element War Paint (Field-Tested)

https://steamcommunity.com/market/listings/440/Strange%20Miami%20Element%20War%20Paint%20%28Field-Tested%29

Starting with August 2020 sales.

Dividing by the average price of a key on that day.

1 sold on August 15th:

$78.47/$2.43 = 32.3 ~ 32 keys

1 sold on August 24th:

$79.19/$2.36 = 33.6 ~ 34 keys

1 sold on September 3rd:

$79.85/$2.32 = 34.4 ~ 34 keys

Current seller:

$86.94/$2.33 = 37.3 ~ 37 keys

https://marketplace.tf/items/tf2/17213;11;w3;pk213

Starting with August 2020 sales.

Dividing by the average price of a key on that day.

1 sold on August 6th:

$64.99/$1.85 = 35.1 ~ 35 keys

1 sold on August 11th:

$69.99/$1.84 = 38 keys

1 sold on September 8th:

$79.19/$1.83 = 43.3 ~ 43 keys

I traded 35 keys to get myself one.

https://imgur.com/a/S6yV0RU

Here's the item history:

https://backpack.tf/item/9040602393

My compare link:

https://backpack.tf/profiles/76561197970757009#!/compare/1601856000/1602374400

My friend's compare link:

https://backpack.tf/profiles/76561198235265356#!/compare/NaN/1599350400

Outlier: 43.

In conclusion, I will be taking 32 - 38 keys as the range.