Magento E-commerce Site Build

I need a full-featured online store built on Magento. The project covers everything from installing and configuring the latest stable release to delivering a storefront that is fast, secure, and easy for me to manage. Core requirements include a modern, mobile-responsive theme, intuitive product and category management, multi-step checkout, integration with major payment gateways, and basic on-page SEO setup.

To keep things clear, final delivery will be accepted when:
• the site is live on my hosting with HTTPS enabled,
• at least five sample products demonstrate configurable, simple, and grouped product types,
• test transactions run successfully in both sandbox and live modes, and
• admin documentation (short screencast or PDF) shows how to add products and process orders.

If you prefer specific Magento extensions or workflow tools, mention them in your proposal so we can align early.