I am an avid reader of urban fantasy and am well-versed with the genre's tropes and cliches, and the Dresden Files is one of my favorite series. I must admit, though, even if it's a mark against me, I've read more shapeshifter urban fantasy than vampire. Still, I have experience as a beta reader/developmental editor, and I have worked with multiple authors.
An edit with me is a multiple-pass endeavor, hence the three weeks to the bid. The first pass takes week. During this week, I will comment your manuscript, and these comments are on overarching themes, plot elements, and structure. At this point, if necessary, I will ask questions about the directions you are taking in your manuscript and what your goals are for the narrative. The manuscript will then be sent back to you for review.
I will make continued passes for commentary until it is agreed that the manuscript is ready for polish. At that time, I will do a polish pass and perform line and copy edits.
My concern is that editing a book is not a swift endeavor. Additionally, I do not know how close you consider your manuscript to be to a publishable state. If the manuscript is close, then the editing process might take a little as two weeks. If the manuscript needs a bit of work, then this could be a month-long (or more) process. Also - are you aiming for traditional publishing or self-publishing, and in what country?