It would depend on what you want/need.
You need to write a list of features as some are easier to implement than others, you also need to think about ease of updating, if you are going to need updates every week then it will need to be designed for this. Do you need e-commerce? If so you will need third-party credit card handling and they will supply the software to impliment this.
The company that I work for has a fairly complicated site that was developed for us by click here but there are lots of people doing this work. I advise you to design an outline site ( a page layout in Word will do)or choose one from the web that you like as an example and give your designer that as a head start.