That’s a 100% valid concern and some content just can't be easily repurposed. We’ll tell you upfront if we feel it’s not going to work so that neither of us wastes any time.
You can send us your blog posts URLs, blog posts in .docs, .pdf, articles, white papers, ebooks, presentations, even drafts of any content you have. The only limit we have is that the source material is under 2500 words.
You can also take a look at this blogpost that will give you a hint what type of content is great for repurposing.