We did the same with our mother in 1995, at her request. She was a Navy vet and catholic so we rented a casket to hold her ashes/urn for a brief catholic service. Her ashes are kept in a mausoleum in New Orleans right beside I-10 and the railroad underpass which floods during hurricanes. I went check on her ashes after Katrina but her tiny vault was high enough as not to flood. The building did flood 2 or 3 feet. Gator posting this about his mother has made me think about going visit there to check. My father is buried in the ground right off Canal Blvd and City Park Ave, since Nov 1963. He was a Captain in the US Navy @ time of death.
I need to do a will soon and will opt for cremation too. Less fuss and expense.
After getting a Notary stamp on them I gave a copy of the wills for my wife and myself to my primary care Doctor, Attorney and the person responsible for taking care of our business.