Handling/Processing Percentage

[SpinThis!]

We need to add a 3% handling/processing fee to all orders...

 

I hacked one of the handling fee order total modules which works except for the products that we *don't* need to charge sales/event tax for-- in other words, it's charging the tax on the handling fee when there isn't any tax on the product itself. Anyone know a way around that?

 

Previously, I set it up so the handling fee was a "tax" by itself but for accounting we need to separate the tax and handling on separate lines... OSCommerce would just put them on the same line...