I think it also depends on what kind of experience you have.
If you don't have (much) experience with webshop systems it might be easier to setup a CMS system with a webshop module.
If you do have some experience with such systems or just a broad experience with webdesign you might be willing to setup a website using Prestashop for example.
I think most systems are not optimized for 'one page websites' so I guess you will have to do some tweaking yourself. (read: not sure, I might be wrong)