Not too many entries ago, I wrote an entry on how much to charge for writing. Since then, I’ve come across a few helpful articles on the topic. It’s rare that you’ll find actual rates outside of Writer’s Market and an $100+ ebook. Too many factors and variables can affect the quote.
The best way to learn is from experience and learning about the process of coming up with a quote. I edit graduate theses (edit, not write it unlike those term paper mills).
The first time I landed a thesis editing project, I charged too little. It far took more time than I expected. The second time, I quoted a better rate… but still short of what it should be. By the third time, I had it figured out plus I had a backup in case a couple of rounds of editing turned into 30 revisions.
The following sites explain the process of coming up with a quote (some are general articles for different service-based business and some are specific to those in the writing business):