wallace4 said:
Most of all I'm interested in the conditions that are offered for the author in this case
For the deals made to authors it varies tremendously. What's included in the deal? Especially what is in it around marketing and distribution costs? How big is the advance? How well known is the author? What's the expected demand, revenue, and profit for the book? Details are everything.
An advance for 5,000 dollars is different from an advance of 20,000 or an advance of 100,000. An advance to a first-time unknown author will be different from an advance to an established low-profile author, or for an established high-profile author. Costs will be different if the publisher is required to meet minimum marketing thresholds and distribution thresholds, and what those thresholds are. Payment will be different if there is an agent involved, they get a cut. There are generally different terms for paperback, hardback, and ebooks because each has different costs along the way. Etc. Payments may be anything from monthly to semi-annually. (For comparison, I get quarterly royalty statements, my last check was 52 dollars as sales are almost completely done and I'm not publishing anything presently.)
As for terms of getting money, there are several phases.
For the first phase, if the author gets an advance they are typically tied to milestones and deliverables, just like in games and other industries. Submit a portion of the content and get a portion of the money, submit revisions and get a portion of the money, submit the final and get a portion of the money. This money is given directly as an agreed-upon transfer or check.
Once the book is being sold, there is a phase of earning out your advance. You will receive a very low royalty rate since the company is basically recovering their investment. Details will matter, it may be 5% on a paperback, it may be 15% on an ebook, but the sales are paying the costs of goods, paying the loan they gave you, paying an agent and third parties, and paying the publisher for their ongoing work. They might keep every cent until the advance is fully earned out, they might give you a small amount of money, or it might just be a low rate. Most contracts still give you royalties checks at this point, but it's small. The amount you receive is based on sell-out, sell-through, and returns, and then you get a percentage as a periodic check or a statement saying thresholds haven't been met.
After you have earned out the advance you're in the next phase. Basically the advance is repaid, the costs of actually publishing the book is recovered, and you're basically switched to maintenance and additional printings. The rate will be higher, but still keep out costs for the publisher to do all their work, handle returns, and so on.
There may also be graduated rates between them.
Maybe you have a pretty good deal on a hardback textbook, getting 10% of the retail price until the first x copies are sold, 12.5% on the next x copies sold, then 15% after earn-out. Or maybe your cheap paperback rates are 5% on the first x copies, then 10%. Maybe it's an online book with no costs for manufacturing, distribution, and storage so your deal might be 10%, 40%, 60% thanks to no inventory. Every deal and every publisher is different. It gets extra complicated by corporate deals and sales discounts, plus bookshops buy at about half the cost of the cover price, and may return books that don't sell. Your book may cost 2.00 per book to print, bind, and box plus whatever warehousing and distribution cost, may have a recommended price of 25, costs gets sent to stores for $12 per copy, B&N is selling with a 30% discount for 17.50 per copy, Amazon at 40% discount for 15.00 per copy. Your contract may give you 5% of the first 5000 copies (that's a lot of books), so you get 3,000 dollars even though customers paid over 80,000 to retail outlets for what should have been the recommended selling price of over 100,000 if they didn't have discounts and sales rates. A year later you may still be selling a bunch of books, maybe you're on your third printing, not a bestseller but well received. Somehow you have another time period where customers paid about 80,000 to retail outlets for the dead tree editions but this time you're making 9,500 in royalties from it.