Book editing needed

We are looking for someone to edit a book on a religious theme. We are looking for grammatical editing, contextually the book is in good form. It will require some extensive grammatical editing. The author is not a native English speaker, however, he has put together a very good message. It just needs to be cleaned up for publication. This same author has a few more books in the works, so give us your best price (and we may have a few others who need editing, as well.) We need good grammatical editing so only bid if you can edit this work using quality, English grammar.