SPA Girls Podcast

How To Diversify Your Income ft. Craig Martelle (EP#572)

SPA Girls Podcast

Show Notes

This is a concrete, numbers-heavy conversation about what diversification actually means for a working author. Million-selling author Craig Martelle has published over 200 books since 2015, across 28 series, and has around 25 different sources of income. Craig’s definition of Author Diversification is multiple revenue streams, and he counts formats, distributors, languages, genres and co-authors as part of it. He walks through where to start when you’ve only got five books out, why paperback belongs in your Amazon ads, what a SAG-AFTRA narrator really costs and why he pays it anyway, and how he translated nine books into German for almost nothing using three AIs checking each other.

Craig is also very open about his pace pace of publishing. In 2019 he published 30 books in 30 weeks, quadrupled his costs, halved his revenue and ended up having heart surgery the following January. He publishes 12 to 20 books a year now, reads every word of every collaboration, and takes the dog out for two hours a day. The three medical thrillers he co-writes with a surgeon are his current bestsellers, and every dollar they earn goes into an investment account for his grandchildren.

And the golden nugget is the best argument against perfectionism we’ve had on the show: if you rewrite one book ten times you still have one book, but if you write ten books you have ten books’ worth of experience.

In this episode:

From Marine Corps intelligence and Russian linguist work to law school to full-time author in October 2015

Over 200 books, 28 series, and roughly 25 separate sources of income

Buying his first series back from its traditional publisher — and earning the buyout fee back in one month on free YouTube audio

Audiobooks on 40 distributors, plus 70 to 80 titles in libraries while staying in Kindle Unlimited

Why genre counts as diversification: readership ceilings and burnout in a single niche

“Write with the reader in mind” — the Venn diagram of what you know and what people actually read

The first step with five books out: one genre, one series, and learning read-through

Where to diversify next, and how to choose an adjacent genre

Translations and which markets are worth translating for, and which ones aren’t

Formats first: why paperback and a full-wrap cover are the cheapest diversification there is

The Amazon ads trick — bundling ebook and paperback in one sponsored ad to drop your cost per click

Crowdfunding an audiobook you can’t otherwise afford, and the snowball effect across campaigns

Why some books sell and some don’t

Marketing the backlist

Resources mentioned INaudio (Voices by INaudio) · Chirp (BookBub) · Kindle Unlimited & KDP Select · Kindle Countdown Deals · BookBub featured deals · Kickstarter · BackerKit · SAG-AFTRA · DeepL · Learn Self Publishing (AI translation course) · Baen Books · Become a Successful Indie Author · the A Surgeon’s… medical thrillers with James Toouli · the I, Soldier military sci-fi series · Battleship Leviathan · the Ian Bragg thrillers

About Craig

Craig Martelle is a science fiction, thriller and fantasy author who has sold millions of books worldwide.

Before he became an author, he had a long career in the Marine Corps, specifically in the military intelligence community where he worked with most of the U.S. Government’s three-letter agencies. When he retired from the Marine Corps, he attended law school, graduated summa cum laude, and went into business consulting.

Craig was also the original organizer of the 20Books Conference in Las Vegas, which he ran for many years, and he now organizes writing retreats for both beginner and more experienced authors around the world. He also writes non-fiction to help indie authors be more successful in this industry.

Through a bizarre series of events, Craig now lives in in Fairbanks, Alaska. He says he never expected to retire to a place where golf courses are only open for four months out of the year, but he and his wife get to watch the no

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