I think the best way to have no duplicate content is :
1 - Create original product descriptions
2 - Create unique Title and Meta tags
3 - Care exactly in the list of products
4- Create canonical URLs and not index all the pages of your ecommerce site
5- Make 301 redirects in case of site redesign 6. Use duplicate content measurement tools
Some tools :
PlagSpotter, to locate online pages that copy your content. You can also use Copyscape, a reference tool.
Webconfs, which determines the similarity rate between two content already online. You can also use the Duplicatecontent tool.
Web SEO Analytics, which calculates a duplication rate between the content of two URLs.
Positeo, which allows among other things to check the duplicate rate of offline content (which has not yet been published on the internet).
Plagiarisma allows the thing. DupeCop, which allows to compare the duplicate between several offline texts.
Siteliner, which allows to know the internal duplicate rate on your site.