Simple E-Commerce Website Build

I need a clean, fully functioning e-commerce site set up from scratch. The store should let me upload products easily, display them attractively, and guide customers through a smooth checkout that accepts the major card networks as well as PayPal or Stripe. I am open to the platform you recommend—Shopify, WooCommerce, or a custom stack—so long as it stays fast, secure, and simple for me to manage once you hand it over.

Key deliverables I will test before sign-off:
• Responsive storefront that looks sharp on desktop and mobile
• Product, cart, and checkout pages wired to a live payment gateway
• Dashboard where I can add / edit products, prices, images, and inventory without touching code
• Basic on-page SEO and speed optimisation so pages load quickly
• Clear hand-over notes or a short walk-through video that shows me how to keep everything running

Please show at least one live e-commerce project you have built, point out what role you played, and tell me roughly how long you expect this build to take. If you have a preferred toolkit, let me know why it fits this job best—otherwise suggest the stack you think will scale as the catalogue grows.