Unless you're in a very restrictive state, why the police? The customer was upfront with the bank.
Community bank - a gun collector rented a large SD box - they were seasonal and preferred not to leave some valuable guns unattended during the summers, besides being secured, temperature and humidity controlled, etc. Several pistols were 1700 and 1800 museum quality worth $100K + each.
(No, he did not show them around the bank - knowledge as a family friend)
Integrity. With it, nothing else matters. Without it, nothing else matters.