Raise Domain Authority to 60+

My e-commerce site relies heavily on product pages, yet its current Domain Authority lags far behind our competitors. I want a proven SEO specialist to chart and execute a clear, white-hat roadmap that will push the DA past 60 and keep it there... (Budget: $250 - $750 USD, Jobs: Content Marketing, Internet Marketing, Keyword Research, Link Building, Marketing, Moz, SEO, SEO Auditing)