Does maximizing the SEO potential of a large site or group of sites require an agency/team or can a single person do it alone?

Selected answers from the Dumb SEO Questions Facebook & G+ community.

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  Devin Peterson: Does maximizing the SEO potential of a large site or group of sites require an agency/team or can a single person do it alone? (assuming that person is knowledgeable enough). I am trying to figure out at which point do I need to call for backup, or will combined efforts pay for itself through the increased effectiveness? Or are there a lot of solo freelance SEOs who manage many sites (big and small) all by themselves?
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  Chris Ashton: Assuming you have a good understanding of modern SEO, that one really comes down to a question of time.
  
  Provided you have the time theres no reason why you couldn't get some great results for a a large site but the larger the site, the greater the effort required. Also consider what would happen if some "emergency" fixes were needed; can you afford to drop everything and react straight away?
  
  Its about more than just the time spent making changes too - SEO is constantly changing and when you're applying your updates to potentially thousands of pages, you need to know you're doing the right thing.
  
  Keyword-stuff the page titles of the local bakery's 3 page website and they might drop a bit but daily traffic and conversions are minimal. Do the same thing for someone like Amazon and you're playing with millions of dollars of potential income.
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  Chris Smit: It's important to keep your focus if you're doing it yourself. And to keep track of what you've been doing.
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  Edwin Jonk: From the expert panel in this weeks SEO Questions hangout on air on 01:59:11 into the YouTube video: https://dumbseoquestions.com/q/does_maximizing_the_seo_potential_of_a_large_site_or_group_of_sites_require_an_agencyteam_or_can_a_single_person_do_it_alone +Devin Peterson
  
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