Visit in different seasons. Understand access, parking, noise, local demand and what guests actually come for. Before committing, ask the planning authority whether your proposed use needs permission.
One practical next step.
Make a list of the costs and limitations you cannot change: location, layout, access and major repairs.
This information reflects my experience and my understanding of published guidance. It is provided for general information only and should not be treated as legal, tax, planning or financial advice. Regulations can change, so always check the current official guidance.