Website design of the look and feel

I would like to have an appropriate design for a Church Website. We already have the site, hosting and a website programming person. He is not very good at the design side, so I want a designer to deliver a design with the appropriate look and feel for us and hand that over to us when its finished. How much will you charge for this kind of work? How many hours work do you forsee this will be, what will be included and what will be excluded for the rate you charge?