Yeah, this is set up slightly confusingly.

Say your project is to fund a print run of books, and the printer quoted you $2000. Plug that into the Project Cost.

Then set up an Incentive item for the printed book. The Cost of Incentive will be ONLY the shipping cost of the book, NOT the book unit price PLUS shipping, as I originally assumed. Why? Look up top at the Total Incentive Cost line. The total cost of all incentives is added up and listed here, so if you add the unit price of your new book in the Cost of Incentive box down below, you’re effectively factoring that cost into the calculations TWICE.

So really, the “Cost of Incentive” box on each line is how much ADDITIONAL money (beyond the Project Cost) that it will take for you to deliver each Incentive.

Further example: let’s say you want an Incentive that includes Book 2 (the one you’re Kickstarting) and Book 1 (which you already have a huge stock of). The Cost of Incentive would just be the shipping cost to ship that two-book package: the cost of printing Book 2 is already accounted for in Project Cost, and the cost of printing Book 1 is zero because you already have it. So the additional cost is just S&H. Then, of course, you just have to set the Donation Required value high enough to make sure you’re turning a profit on each Incentive!

Pretty handy tool — but could use some more detailed instructions.