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Thanks, it worked

Make them relevant to the site & valuable to the users seeing them.

Don't make them just say "Click here for linkbest broker Seattlelink" but create something cool for the visitors of that site, like "Check out Johns 2 minute video guide to picking the best broker for your financial situation"

That way "link juice" from those sites will just be a by-product from doing this & you get considerable value with referral traffic as people actually click through those links.