Customizing Invoice Items and Calculated fields

Customizing Invoice Items and Calculated fields

I've just started evaluating Invoice and have a couple of needs.

1. Items - Most of our Items are in one of three categories; Hardware, Software, Services. I would like to add a pick list field called Type and enter one of these values. I would then like to list the Hardware in its own section with a total, the Software in its own section with its total.

2. Calculated Field - We would like to create a "Deposit Required" field that is 20% of the Hardware subtotal.

Is any of this possible?

Thanks in advance.