There are lots of documents you may or may not need. Birth Certificates, Social Security card, Medicare card, health insurance card, insurance policies, marriage certificates and divorce decrees for all events, any deeds or titles, bank accounts, credit union or any financial information, credit cards (numbers and etc.) automatic payments for services. It really is worth hiring an attorney if dealing with property or larger estate in my opinion. Once they pass get several copies of the death certificates as most insurance companies and financial institutions will require them. If you feel you have 5 years before they pass or even before applying for Medicaid a trust in many states will be worthwhile so again contact an attorney or estate planner so prearrangements can be made. It is a lot easier and cheaper to plan ahead but still a very difficult task to get done.