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We were recently approached by a SEO agency saying that we had a bunch of very toxic links. They wanted to do the work for us but we've decided to keep costs down and keep it in-house. I've downloaded a list of the links to our site from Google Webmaster Tools and am now manually going through each link to find the links we want removed/disavowed. What is the best way to judge the links? Please note: I have limited resources. I'm using a combination of my gut and SEO Moz's Domain Authority. If the site or directory is irrelevant and has a low Domain Authority I put the link in the remove pile. If I come across a directory that doesn't seem too bad and it has a reasonable Domain Authority I leave the link. Am I doing enough?