Book Printing is a difficult business. But now it becomes very easy to print books. Printing on demand can also be done. All you need to do is follow the points listed like Ask the author, Ask around, Reputation, Editor, Payment method, Contract, and Financial term.
Ask the author: Sometimes it has been observed that the author considers some publishers lucky for him or he wants the publisher to publish his book. If you are looking for quality book printing online then you can check out https://www.inhouseprint.com.au/.
In this case, it is better to consult with the author before deciding the publisher. If the author comes to you and says print my books, then you have to take his words.
Ask Around: Take instructions from your family and friends. You can also find help on the Internet and search online for good book publishers. Look at the books and look for the publisher who has published them. Ask your colleagues if any of them have issued a patent or know the publisher.
Reputation: Check the reviews of the authors who have published their books from this publisher that you will choose. Select the publisher that has good reviews. Don't try experimenting because the sale of your book will be at stake.