Second try with a more accurate price range. Thanks to all the people that helped me with this research.

Sale 1

31/03/23 one sold at marketplace.tf for 899.99 USD, taking key as 2 USD that's almost 450 keys. Neverthelsess, current sale listings at backpack.tf start at 400 keys, that's the reason I'm not considering within the range price.

Sale 2

30/03/23 it was traded + Green Energy Merc's Mohawk for a Purple Energy Large Luchadore. Proof. PS. I'm currently updating the price of PE Large Luchadore to 450 keys with this suggestion.

Sale 3 (using it as min)

08/05/23 it was traded + 2 keys for a Houwar + Refragmenting Reality Bumble Beenie. Proof

I was able to contact the previous owner ([TGP] Crust), he told me he dumped the Houwar for 283 keys and was able to sell the Refragmenting Reality Bumble Beenie for a mix offer of 37 keys (7 keys, smaller items added up to another 9 keys, and a australium pro ks force a nature he sold for sold for 21 keys), that's 320 keys. Proof of my chat with him

Sale 4 (using it as max)

10/05/23 the same Sunbeams Le Party Phantom of sale 3, the guy who bought it, Kozy 🫐, re-sold it for 360 keys pure, that's what he told to the previous owner ([TGP] Crust). Proof. Proof of the chat I had with [TGP] Crust

Other Phantom

- https://backpack.tf/item/466243412 duped, I contacted the big cheeze. Proof

- https://backpack.tf/item/300789581, it seems the previous owner sold his entire backpack for cash.

- https://backpack.tf/item/279646426, the guy only exhanged the hat with his alternative account so there was no sale involved. Proof

- https://backpack.tf/item/226080565 duped, this is the one [TGP] Crust sold to Kozy 🫐, then he resold it to Keksi and he asked someone that is brokering for 400 keys.