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Don't worry too much about DA of the site's you're getting links from. A natural link profile is a mixture of volume and quality. A natural link profile for a new site should include directories, forum links, guest posts, social links. Although these types of links are not important for an established site, it's important for a new site. But online PR on hyper contextual content is the most important factor, even if the site has a low DA but it highly contextual, you should go after those links. Focus on contextual online PR.

It's not uncommon to take more aggressive and less "natural" link building tactics for a site that is relying on self-funding or needs early growth. I've seen sites start out with unnatural links then safely transition to a "natural" link profile with high value links from key publications later to develop stability. This approach can work to drive short-term success with avoiding the potential long-term issues.