When building websites there are many factors to consider:

Website Maintenance:
    How often the website will be updated?
    How will the website be updated?
    What areas of the website need to be updated regularly?

Dynamic Content:
    Will the site require a database to catalog items, products, etc?
    What kind of secure area will be required for editing the database?

Anti-Spam Techniques:
    Do you want to use forms for email submission?
    Do you want to use other methods to protect published email addresses from spam?

Search Engine Performance:
    Will the navigation of the website be in HTML?
    If using a Flash based navigation will there be a text based alternative?
    Will the text of the website be in HTML or Flash?
    Are you using HTML frames?

Design:
    Will the website be graphically intensive?
    What Internet speeds (Dialup, High-speed, etc.) will your users be connecting with?
    Will people be connecting to your website via mobile devices?
    What is the minimum size of the screen the website should be viewed on?
    Should the web page scale to the maximum page width?