I'm trying to work out a formula so I can do an exel spreadsheet to work out if I'm actually making a profit but just don't understand the paypal fees (and the website has not enlightened me). From the paypal site it would seem that I am charged 3.4% of the amount + 20p. So.......on a 99p final value + £1 p&p I have a charge of 27p. Please someone explain how this is arrived at.