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I would advise you to use Foundation and then swap out the parts that you're not using. You will have less work with replacing Find and Personalization than building a site from scratch. Magnitudes less. It's essential to understand that CMS and Commerce "out of the box" is just an API and a backoffice UI - there is no site, no controllers, no display templates, no nothing. Foundation gives you a great place to start, with everything set up - a fully functioning site, according to best practices, with a working build system etc. You basically just need to change the frontend/styling and replace the backend parts/integrations that your customer require. Good luck!