Who should I hire for SEO services, and who is considered the best in the industry?

Is there a specific time to post on Instagram to get more engagement?
I’m looking to hire someone with excellent SEO skills without overspending. I need references, as I’ve tried on-page SEO and blogging but haven’t ranked over my competitors. Who do you recommend, and what’s the cost?

For Instagram engagement, posting times can vary, but generally, evenings and weekends tend to have higher engagement rates.