Sometimes it's the simplest of things that prevent your pages from ranking well. Are your pages getting found and indexed by search engines? If not why not? You could be unintentially signalling that they are "noindex" in a variety of ways. Or, your site architecture may be making it difficult for search engine bots to efficiently crawl and find all of your pages.
If your site is throwing a lot of server errors, or pages are loading slow, Google this can punish your domain and have a negative effect on ranking.
Have you changed your URLs and not set up 301 redirect directives so that search engines understand the change?
Do you have a high "bounce rate" do to a confusing page design and a UX that your site visitors stumble over?
E-commerce sites often have issues caused by massive duplicate content, or "cloaked content" that users can't get to but search engines can find. Whatever we uncover in our audit, we'll deliver our recommendations in ranked order of priority. Some fixes are definately more impactul than others. We'll explain why, and we won't try to snow you with developer-speak. If we can help you better understand the technical fundamentals, you'll be beter equipped to avoid problems in the future.