Technical SEO is the foundation of your search engine optimization, period. Your site must be crawlable before it can index in search engines and eventually rank. If your site has technical errors, all the "great content" in the world cannot help your website.
A Screaming Frog crawl can help you see all the 404 errors, redirects, canonical tags, title, and meta tags, on your website (and much, MUCH more!) It is an ultra powerful tool in the hands of an SEO, and for a price, I can give you some valuable insight into your website's search engine crawlability.
I send you a Screaming Frog crawl up to 20,000 URLs. And Give you in colored excel sheet.
Crawl your complete website. And Give you in colored excel sheet. It will have extra's charges. Please discuss via inbox.