Website using javascript

We need to build a custom website. There will be around 8 pages which we will design and provide: - Home, About/Bio, Get Started, How It Works, Services, Packages, Testimonials, Contact The functionality we need includes: login/account, Checkout Cart (using our color scheme), the ability to buy 'credits' and 'gift cards', newsletter sign-up and customer aggregation, Contact Forms, etc? Please provide estimate of time and best platform we should use. (HTML, Wordpress, Javascript). We like the look of this example site: [login to view URL] ****