I know John's opinion about WordPress, but it sounds like you are looking for Woocommerce. - Open Source - Thriving plugin ecosystem - WordPress.com can host i

I know John's opinion about WordPress, but it sounds like you are looking for Woocommerce. - Open Source - Thriving plugin ecosystem - WordPress.com can host it for you for $300/year and it will take any traffic you throw at it - It has full advantage of WordPress which is the most popular CMS on the planet