The figure I've seen is about 10% of the cover price. So if your book is selling for $10, expect to make $1 for every copy sold.
I think everyone here will tell you don't go house-hunting just yet and that you should write for the love of writing. While some people in this world may have the secret formula and the skill to transfer it to best selling books I'd say 99.9999% of writers don't. If you are thinking your story is so great the world would be mental not to buy it then great, keep writing and hopefully some agent will think alike and tout your work up and down Publisher Street. My advice for now, write and write and write. Experiment with different characters and scenes and situations. When reading, take apart every sentence, every paragraph, how the author structures his/her work. Take notes of what you love, what you hate, what you would do different. See how they do things, how they move you, how they lied on the back cover, how the critics got it wrong. While your writing maybe be mature for someone your age and above that of your classmates and peers remember you are still very young and you have all your life to write that perfect book - then you can sit back watch the dollar signs rack up while you write another!
You can Google this subject and you'll find a myriad of answers. It depends on who's publishing it, what kind of deal get, and how sales go. But honestly, don't worry about it and don't quit your day job. Write, write, and write some more. Do not take peanuts for your work and one day you'll be skilled and respected enough to get a fair deal. Although, I think I read this in the writer's market book, the average first timer can get 1000-5000 (the higher being very very less likely) plus some royalties on wholesale or something. But if you're writing to get rich, you're in the wrong business, imo. Earning money from writing is an endgame occurrence that you build to like street performers one day having a sold out amphitheater just for themselves or garage bands playing at little shows to eventually opening for big names and one day being a big name. I am rambling!
I forgot to mention advances in my first post, so I'll do it now. Popular writers can get fairly large advances (even 6 figures). It's rare for a new author to get a large advance, though not impossible. I'm not sure what the average advance is for a new author, but I'm guessing 4 figures (someone check me on that).
I think that it depends on your definition of "relatively successful." I've vaguely assumed that a substantial majority of books earn less than ten thousand US dollars for the author, perhaps less than five thousand, but I have no idea where I originally got that number.
I'm with @erebh on this - I wouldn't concern myself with this just yet, and for a number of reasons. The publishing world is changing rapidly, and there are more options for a writer seeking publication than ever before - self-publish or traditional publish? E-books or hardcopy? Agented or unagented? Each choice involves varying risks and rewards, and in the end your demeanor, values and expectations will shape the choices you make, as well as the area in which you decide to write. Besides that, the publishing world will likely further evolve between now and the time you decide to publish, and so choices you might make today could be very different by the time you are ready. All of this is secondary to the main concern, which is that focusing on the publishing process (whichever variation you choose) and trying to gauge expectations now can only serve as a distraction from your main concern, which should be developing your writing skill. The basic dynamic is that the more copies you sell, the better you'll do (yes, I know you know that), and the fact today, which will probably continue to be true tomorrow is that it is extremely rare for a first novel to do well, and so I would be very skeptical of @thirdwind's estimate of four-figure advances for a first novel. I would expect no advance on a first novel. I believe the current royalty rate for a traditionally published novel is about 10% (@mammamaia would be able to tell you with greater certainty, I'm sure). If you have an agent (another discussion for another day), they would get 15% of your 10%.
There is one where I think that it particularly matters, though: Authors who think that hiring a copyeditor or other services will get them published should realize that even if that works out, odds are that they will earn less from the book than they paid the copyeditor.
Ah, thank you. I don't think I need/can afford/have time for/want to deal with an agent/editor, ahaha. I wasn't expecting that much (if I wanted money I would be in another line of "work") but it's nice knowing I can make a decent profit.
Just to make it clear, an agent wouldn't charge you anything, and neither would an editor at a publishing house. I'm talking about an author hiring an editor specifically to go through their manuscript correcting errors that the author should learn how to correct himself.
The only times a first timer get's well paid is if the book is a huge success out of the blue or the publishers believe they found some sort of rare gem. Most of the time, working full time at minimum wage will earn you more than what they pay for the rights of your book.
first of all, it depends on what kind of book... fiction or nonfiction?... pb romance, or hard cover action thriller?... self-help/how-to or memoir?... and so on... next, on who you are... a world-famous bestselling author with the latest in a bestselling series, or new unknown writer with a first novel?... a renowned expert in the book's field, or an unknown nobody who's faking it?... a movie star with a tell-all memoir, or someone nobody's ever heard of with an angsty rundown of a hum-drum life?... and so on... third and finally, who your publisher is and what your contract stipulates in re advance and royalties...
