By default, the values you see on the miscellaneous fees when you initially setup tests are pulled directly from your Amazon account, so there is no need to change these. However, if you want to double check your FBA fees, here's how to do it:
In seller central, go to Reports > Payments.
Then click the Transaction View tab.
Click on an order, and the FBA fees are found on this page, that looks like this:
In addition, we will also ask you for the unit cost. The unit cost is the total amount you have spent on design/research, manufacturing, shipping and anything else you can think of excluding FBA fees.