Hi,
Greetings,
with responsive theme, customize it as per your need including category, sub-category, listing, details, payment gateway and let me know how many products will be there, what kind of products and whether category, sub-category will be there or not accordingly I'll select which CMS to be used either wordpress or opencart or magento and execution time will suggest accordingly.
kindly revert with your availability to discuss in details.
Regards