I bought this hat for 32 keys. Immediately sold it to a collector friend of mine for 35. According to https://backpack.tf/u/76561197995915986 (price mod), buying an item to sell to someone immediately is considered brokering so this brokering of 3 keys extra is not going to be included.

Proof I bought it for 32 keys:

https://imgur.com/a/CMhumOG

https://imgur.com/a/y8TDRh6

Proof I sold it for 35 keys.

Spidda's screenshot: https://gyazo.com/a33d74a5e9c174cf7ff06d432ef1e694

My screenshot: https://imgur.com/a/h22eoWE

Taking 32 keys.