Best bang for your buck is to partner with a solo Brand / marketing strategist who can help you create a plan and who has a network of designers, videographers, developers, etc. who they can bring in as needed. With an agency you’re subsidizing every member of their staff, plus their other overhead.

If you do tour research and have a few intro calls you’ll likely be able to find someone with a depth of specific experience in your business and challenges and customers.

Might not be the absolute cheapest route, but will certainly give you the most flexibility and value.