How much do professional proofreading service charge on average?

The internet is crammed with professional proofreading service. There are individuals and companies offering book writing services. You can find writers for any genre or language you want your book to be written in. The book cost depends on the genre and the writer’s experience. An experienced professional can be expensive. Keep in mind that this is only the cost of the manuscript, excluding design and publishing. How much do you think a good writer should charge. I get Advised for Professional Book Writing services