Will the site be coded in HTML, flash or what? Are the images optimized and upload-ready or will the web designer have to prepare them for the web? Will the designer also handle purchasing the Domain Name, securing the Web Host, and Search Engine Submission or will the client be responsible? Is the web designer a professional and provided this client with a client list/sample sites to contact for references?
I've designed and coded numerous sites in my time. Web design ... done correctly ... is a beautiful balance between art and programming; and this artistry and attention to detail does not come cheaply. Depending upon the designer, the complexity of the site and the extras, I'd say $700 is slightly higher but definitely within the normal range of the cost of a pro site these days. Just make sure your friend is vigilant before proceeding and is knowledgeable about what is included in this price and checks out the designer fully.

DeDe