Copy edit 

*correct grammar, spelling, punctuation
*tense
*fact check 
*continuity of actions, location, descriptions
*consistency of spelling, hyphens, numbers,  capitalization
*sentence structure  (including passive voice)
*repetitive words 
​*accuracy of medical situations and police scenarios
*no additional charge to look at blurb or synopsis for  manuscripts I work on

Note: My proofread is just one read, but I will still correct everything listed above if I find it.   In addition, I don't concentrate on developmental/content, but if I find something, I will mention it.

One set of eyes will never catch all errors, so I recommend at least two sets of eyes in the editing process.