Two great sites are http://www.shopify.com/ or http://www.squarespace.com/. The both have content management systems that are build and managed by the companies, have integrations with Google Analytics and best of all they have the whole billing flow/system taken care of, which for a commerce site is one of the most important things to get right.
They provide base themes or allow you (with a little elbow grease to learn their respective templating languages) to completely control the front end.
If this is for clients you get the added bonus directing them to the Shopify/SquareSpace customer service for more backend technical questions about payments etc.
I've successfully helped over 150 entrepreneurs, startups, and businesses, and I would be happy to help you. Please send me more information before scheduling a call - so I can give you maximum value for your money. Take a look at the great reviews I’ve received: https://clarity.fm/ripul.chhabra
