Possible Clues:

• Six feet under
• Six feet (in depth)
• About six feet of water depth
• This six-footer starts to be overweight
• Come to terms with the budgetary excess on unfinished accommodation
• Come to understand the water depth
• Come to understand
• Nautical unit
• 'Full ... five, thy father lies' (The Tempest)
• Measure the depth and ample proportions for Trim accommodation