Kristoffer Mitchell, 56, of Franklin Drive Munmorah appeared in Belmont Local Court before magistrate Peter Barnett on November 20.

Magistrate Barnett and told Mitchell NSW taxpayers were not there to fund his business.

Over six months this year, Mitchell bought 14 vessels, two of which sank and a further six were seized by the NSW government to prevent them sinking or causing pollution hazards.

Mitchell was charged with, fail to comply with a prevention notice, fail to remove sunken vessel when directed and fail to comply with a notice to repair an unsafe vessel.

Unsafe vessels were illegally moored on Sydney Harbour, Lake Macquarie, the Hunter River, and in Camden Haven at Laurieton.

Mitchell, who was in attendance, unrepresented and declined assistance in court from Legal Aid NSW, pleaded guilty to 12 charges for failing to comply with notices to remove the eight vessels, and occupying a mooring without a licence.

NSW Maritime executive director Mark Hutchings said it cost NSW taxpayers $45,000 to tow, salvage, store and dispose these eight vessels which were left illegally on other people's moorings and emergency moorings, often blocking a waterway or partially sinking leading to environmental concerns.

"It's a lesson to all boaties to follow the rules which are there for the benefit of all water users and also a reminder that a $250 fine for a vessel obstructing a mooring can reach up to $5500 once a matter is being considered by a court," Mr Hutchings said.