A new web site typically takes about three weeks (depending on size and complexity of web site of course). It is really impossible to say a small business web site will take 3 weeks without reviewing the necessary items and creating a detailed outline of what all will be done, what order and time expectancies for each. Here is a example of a break down and hopefully this will help
PHASE 1: Create web site outline
The first item would meet with the client and create a very clear outline of what they want and what they need in there web site. This is probably the most important step and if not done properly will cost you a lot of time later down the road.
The client needs to know what will be included for the price they will be quoted. If something is outside the scope they need to know that front and they will either say "Ok add that option" or "No we do not need that" and then it is clear what they will be getting and what they will not.
PHASE 2: Create web site design
Once you are both clear on exactly what all is to be included on the site then you may start the mockup of what the actual site is going to look like. This mockup (I do all of mine in photoshop) will be the blueprint of the entire site design. The mockup will look exactly like a functional web site only it will be a graphical comp of what to expect from the actual coded pages. With this simple mockup we can determine and make agreements with the client as to what the navigation will look like, color scheme, content position, special content item placement (newsletter signup etc), and functional what the web site will consist of. But with it being a page comp it can be easily changed and modified.
PHASE 3: Approve site design and code page templates
Once the client is happy with the look of the site and you have both agreed on the layout and features, etc. Then the next step is to start the process of coding the page templates. Typically I code two main page templates "home page" and "content page" templates. Home page will also be a different layout and include different items then all of the other pages within the site. Make sure you define clearly what is going to be included on each page type.
PHASE 4: Fill in site with content
Once the site templates have been designed then it is just a matter of filling in the blanks. You can then use your CMS (or just regular html templates) and use these shell templates for homepage and content to generate all of the pages within your site.