Possible Clues:

• Fortress constructed on the beach
• Beachfront building?
• Keep on the beach: it will be soon liquidated
• 'Keep it there by the sea until it's tied up, by the sound of it (4,6)'
• Tot's precarious construction
• Model home with an ocean view?
• Keep close to the sea's edge?
• Keep this on shore for the children
• Shore defence goes with the tide
• It's been built for the young on the Strand