If you are interested in having the SEO Audit Tool on your web platform, you can have a free seven day trial of it. By embedding this tool directly on your page, you can generate great leads from your users by seeing their websites or the websites they are interested in. From here, you can target a more specific audience and see great improvements in your conversion rates!
The audit is for all pages and not only one. What happens in the majority of the cases is that pages / posts have similarities so you can group them together. For example the pages of a website may be ok but the blog post pages may be missing titles. It’s a lot of work especially for a 500 pages website but you can start from the most important pages first and work your way to the rest