Specify marketplace commision fee

[OnlyOnePro]

Describe the solution you'd like:
Add a new field to the coin to specify of the cost of purchase how much of that were commission fees. This could be useful for analytical purposes, and if the sell feature is implemented we could use the app as a ledger more than a on-the-spot tracker (which tbh is pretty cool on its own)
Also depending on a configuration CheckBox on the settings page, this could be ignored by the user as losses from that coin (I know it is dumb but I know some people that would love this)

[ismaelestalayo]

I've done a quick test of adding a "Transaction fee" field to purchases, and you can see here how it affects the "Buy price" of the purchase by subtracting the fee from the total cost:

You think there should be a toggle/checkbox in the Settings to set whether the fees should be taken into account to calculate the profit of a purchase?