There are a number of different options for Flat Rate charges for shipping
If you want to charge one flat rate, regardless of how many products the customer purchases
If you want to charge a flat rate for each product the customer buys
If you want to charge a flat rate but then add an additional smaller sum for each additional product purchased.
First step for all of the above is to add a Flat Rate Method to your Zone
To add your cost to the Flat Rate, please Edit the Flat Rate to enter the Cost
If you want to charge one flat rate regardless of how many products the customer purchases, you simply need to write the number in the cost and click save. For this example, I want to charge 5 euro.
Note i am not adding a euro symbol as the website is already defaulted to euro
If you want to charge 5 euro, per product purchased by the customer follow the below image
If you want to add an additional amount per extra product purchased you must follow the below formula. For this example, i want to charge 5 euro for the first product and an additional 2 euro per extra product
The above will charge 3+(2*1)= 5 for the first product, and then will charge 3+(2*2)= 7 for the second and so on.