All projects are different. And your words are important.
That’s why it’s always so helpful to see a sample of the text beforehand.
This helps me in my assessment of how long a job will take and be able offer you a fair and accurate quote.
To give you a clue, my copyediting and proofreading rates are in line with those suggested by the Chartered Institute for Editing and Proofreading (CIEP).
For copywriting (or rewriting), I will charge either by the hour or at a daily rate. My rates are in line with those suggested by ProCopywriters.
And it’s worth remembering that solicitors charge at least £100 per hour. (That’s not to say an editor is ever a replacement for legal assistance should you need it, but using a good editor might help you avoid it.)