well sir we can create a site like your demo site we will provide all the functionality as per your requirement. you need to purchase paypal payment integration then we can integrate in your site. more we will prove you a admin panel by which you can update, add, remove content, pages , product, pictures as well as we will provide you a registration form for user for purchase item.
for more we will take care things of your project completion you can check my completion rate and review also.
thanks
more we can chat here....