Develop a Responsive Online Store (Wordpress/Shopify)

I am seeking a skilled freelancer to develop a functional and visually appealing online store. This is a new project, and I require a solution that is presentable and cost-effective, utilizing a template-based design rather than a fully custom one.

The key requirements for the online store include:

- Support for up to 15 products.
- Implementation of a shopping cart system.
- Integration of a payment gateway (preferably MercadoPago or PayPal).
- Responsive design to ensure compatibility across desktop, tablet, and mobile devices.
- The store should ideally be built using either WordPress with WooCommerce or Shopify.

I am looking for a responsible freelancer with a solid portfolio showcasing previous e-commerce projects and excellent communication skills. While I have an approximate budget in mind, I am open to receiving proposals that align with the project scope and my requirements.