The extent of editing I perform depends on the quality of writing submitted. Regardless of the quality, or my initial impression, I do a thorough line-by-line editing of the material — twice.
With books and Doctoral dissertations, my focus is to ensure consistency and academic soundness, making sure you have addressed all of the research questions and hypotheses, and have discussed the limitations and recommendations.
I edit using “Track Changes,” and send that marked-up version to you, along with a clean copy.