Hi Luis,
Hope you doing great.
Reviewed your requirement & found that The customization that you want may be very not possible through native Shopify as Shopify don’t allow much coding, that only allow limited things, if we want customization we need to create Shopify app and for that you need to become Shopify partner and need to create developer shop as its paid and require hosting to write custom code.
Or In my suggestion you can use Opencart, Prestashop or Magento as they are hosted on our server and will allow more customization then Shopify. Please add me on skype: cis.brenda or mail me at brenda.cis40@gmail.com . Please let me know your inputs on this.
Regards
Brenda