A planning permission compliance check reviews whether the property and any extensions, conversions or outbuildings match the approved plans and comply with relevant conditions. Your solicitor may ask an architect or engineer to inspect the property and provide a planning compliance or exemption letter, while checking the local authority planning records. Any unauthorised work could create issues for a mortgage, resale or future alterations, although the impact depends on the circumstances. Ask your solicitor what checks are needed and confirm uncertainties with the relevant local authority or a qualified professional.