Each Site Builder account is tied to a single domain name however there are absolutely no limitations as to how many different templates you can use with the domain name.
You can change your template as often as you wish with no additional cost.
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How does the site builder work?
The Site Builder is a fully online web site building application that can be used to build your website.
Websites built will look professional and no technical knowledge is required to use the application.
The best way to review the Site Builder is to try it out. Click on the following link and then select “Test Drive”: