Writing the book is art and craft. Selling the book is pure business. The goal is to make money. Every book must make money in every format, no matter how many backers each format has.
I'm using Kickstarter language here, but the same calculations go into book sponsorships.
Round all prices up to the nearest dollar. (Okay, if it's ten cents over dropping it is fine, but be real sure you want to do that. You gotta eat that dime.)
I need two prices for each reward:
This allows setting tier costs so everything always makes money.
I offer seven main rewards when crowdfunding a book
Not all campaigns offer all rewards, but I update my spreadsheets for all rewards whenever I price out a campaign.
This is built on two spreadsheets.
Whenever prices change. My main suppliers are IngramSpark and USPS. Both announce rate changes in advance.
Go to IngramSpark. Pick a comparable book. Get the printing cost for paperback and hardcover. Round up to the nearest dollar. Record those prices in the spreadsheet.
The bundle spreadsheet lists every title and the printing cost for each, generating a total printing cost for the bundle. Make sure the most recent books are on the list and have an IngramSpark printing price. Spot-check printing prices to be sure you didn't miss a price increase.
Get the sample USPS Priority Mail Flat Rate boxes and the reference paperbacks of all the books. Double-check that you have ALL the books. See what combination of boxes you need to ship each bundle. At this time, TWP bundles fit in two Large Flat Rate boxes.
Note the packaging needed on the campaign fulfillment spreadsheet.
Charge retail price for dropshipped print books and ebooks. Crowdfunding backers want to make the book happen, and they want you to eat while you make it happen. What's retail price? Depends on the cut you want to give bookstores. If nothing else, figure it out using the IngramSpark calculator.
Add $5 for signed paperbacks and hardcovers.
For the bundles? Add up the retail price of the books. Knock off ten percent or so. Round it off so it looks like a real retail price.
Enter the prices in the spreadsheet.
As of now, IngramSpark can mail a single book from the US to anywhere in the world for $10. Check the cost to ship to test addresses in Japan, New Zealand, and Uruguay.
Plain shipping costs would be the USPS rate. Don't charge that. If you're signing and mailing a book, you have to touch it. That's work. Charge a little more for shipping and handling. Not a lot. Rounding up to the nearest dollar works.
For backers in the US, ship new books with Priority Mail Flat Rate envelopes.
For backers outside the US, ship new books in 6×9 bubble mailers.
Go to shippo (or whoever you use for shipping). Enter test residential addresses in California and Alaska, or other faraway states. See how much a flat rate package there costs. Round that to the nearest dollar. Some destinations will cost more, others less. Figure out the high end rate to deliver the book. Put that in the spreadsheet for signed paperbacks and hardcovers.
Use those same test addresses for the boxes you need to ship signed bundles. Record those numbers in the spreadsheet by the rewards.
Realize that USPS provides identically-sized flat rate boxes for overseas shipments. Wonder how much it would cost to ship a complete collection of signed books to Australia. Check. Now that you're reminded that shipping would exceed $300, decide to not even offer that as a reward. Even for someone as ridiculous as me, some things are too ridiculous.
You need shipping costs for Europe, Australia, Canada, Japan, and Rest of World (mainly Australia). Australia is the most expensive place to ship to. Fortunately, Aussies really like IngramSpark's AU dropship; books arrive in a matter of days.
You can assume a book is 6×9 and 20oz.
Find test addresses from each country or region. Europe is tricky. Try several countries including Moldova, Germany, Spain, the Netherlands, Ireland, and England.
Look at the prices. Figure out what a decent average high end is. If one or two books are a buck or two over, it's no big deal. If many books are a buck or two over you won't lose money, but you'll wish you had checked shipping costs more thoroughly.
Enter those shipping costs in the spreadsheet.
The margin is the amount you make per book, divided by the book's retail price. Aim for at least 70% margin on individual books, and 60% on large bundles. (If someone buys thirty books, you really do make it up on volume!) You can then use the spreadsheet values to populate your crowdfunding rewards.