There are a lot of factors that dictate how long a website will take to develop. If you have your branding established already(Logo, colors, typography) as well as content that will help expedite the process. The complexity of the website may extend the development timeline also. I have completed websites in as little as 2 weeks. I suggest you plan for 4-6 weeks for a full website to be completed. After a discovery meeting, a timeline will be established and agreed upon.