Both options are possible. Some businesses choose to conduct their own SEO audits in-house using a combination of tools and manual analysis. This can be a good option if you have a dedicated team of SEO professionals or if you have a smaller website with relatively simple SEO needs. However, if your website is large or complex, or if you don't have the in-house expertise to conduct an audit, it may be more effective to hire an external agency or consultant to conduct the audit for you. External agencies and consultants typically have a wealth of experience and specialized tools and techniques that can help to identify and address any issues or opportunities for improvement that may not be obvious to an in-house team.