Unit cost as a percentage of another item?

In some cases, I might need to have add-ons for a particular product, in which the cost is a percentage of the overall cost of the product itself. For example, if I invoice a radio spot at $X for local broadcasts, a regional spot would run an extra 25% or whatnot.

Would there be a way at some point to be able to specify the unit cost for the add-on item as a percentage of the line-item immediately above it (and account for multiple units)?


-Item 1: Description - $200 unit cost x 5 units = $1000

-Item 2: Add-On - 25% of Item 1 ($1000) = $250

It’s not a major issue to just add in the cost by hand, but it would definitely be nice to be able to just set the unit cost as something like “% of above” and be done with it.

Just an idea I thought I’d toss out there.


If you self host the app you could have the feature custom built.