Help to use Fee to add Paypal creditcard fee

Hello All

And thanks for a great componet, I am trying to set something up with the use of Fee

Here is the deal

I have clients that jumps paraschute with me, they book a class for [full amount]

1) Then they only get the option to pay [deposit amount] (I know I saw the solution here somewere anyone??)

2) They can chose "I have jumps that I havent used" (checkbox) and then class is free [fullamount]-[fullamount] (its free)

3) I want them to click on "Yes I agree to pay Paypal Pro Fee of deposit" (checkbox)
And then let the form add a fee to deposit ([deposit amount]*0,034+2,6)

4) And the the "Paypal fee of deposit " shovs up on registration/ confirmation page



Help pointers...??
Site: parawings.com/kurser?task=individual_registration&event_id=3