I took this challenge on 3 years ago as our previous website was awful.
It really depends on how much time and effort you want to put in to it, myself, I loved it and still do to this day.
I don't use any sort of CMS, purely HTML, CSS and JavaScript coding using Dreamweaver, graphics on Photoshop and hosting done through Azure.
Like I said though, it depends on the time you have. Not just building, but also maintaining. I built it within the 6 weeks holidays, along with all the policies etc, maintaining these days can be 10 mins a day to several hours depending on the content that needs creating.
You could start off by playing around with one of the templates of Themeforest, go from there.