The operation to recover firearms at a property in Wyverstone in April has led to an overspend of £160,000 by Suffolk Police.
The figure is highlighted in a report to the Suffolk Police and Crime Commissioner.
Specialist search officers were on the scene at the home of the late James Arnold, a former chairman of Wyverstone Parish Council.
Mr Arnold was arrested but died in July while on remand. He had terminal cancer.
A spokeswoman for Suffolk Police said officers had remained on the scene for four weeks to ensure public safety while weapons were recovered and evidence gathered.