Before the building inspector arrives, be sure that the work to be inspected is completed in compliance with your plans and any relevant code requirements, that your inspection card and plans approved and stamped by the County are at the job site, and that the necessary access for inspection (including a ladder if needed) is provided. If the building is occupied, make sure someone is at home to let the inspector in. If any tests are required, make sure they are ready so that the inspector can observe the outcome (e.g. for a gas piping test the inspector would need to observe a pressure gauge showing the pressure holding steady after the gas lines were pressurized).