A friend of mine recently died without leaving several very important documents. His wife is at her wits end trying to get through it.

I have a ring binder in my desk with the label "Where Everything's At . . . And How to Open It." I has pretty much everything my wife & kids need to know about -

Where the money is - Passwords, account numbers, web links
How to access the checkbook and investment spreadsheets (I still use Lotus 123)
Where to find the will, financial power of attorney, and healthcare power of attorney (advanced directive)
Location/serial number/purchase receipt for the guns
Insurance policies
Key to the safe deposit box
Month by month list of what bills come due (utilities, quarterly IRS payments, insurance)
How to freeze the three credit reporting companies
People to be notified in case of my death
Instructions for my funeral (I better be wearing my Hawaiian shirt)
How to check breaker box for tripped circuit; how to turn off water line from street

They all know it's there, and it's backed up on a flash drive for each one of them.

If you don't have a will, the state will decide who gets what. If you're married, it's pretty straightforward that your spouse gets it, but if not, it can get complicated.

A financial power of attorney allows your spouse or kids to access all your financial accounts. If you don't have one, your accounts may be frozen for an extended period.

A health care power of attorney (advanced directive) allows you to make decisions about your wishes concerning when to pull the plug; otherwise some hospital administrator will do it for you.

These three documents: will, financial POA, healthcare POA will probably cost you $1,000 - $1,500 done by an attorney. The do-it-yourself method is to find state-tailored templates on the web. Not as good as an attorney, but better than nothing.

The wife died just shy of a year ago and even when I knew where everything was there were still issues.

The social security folks don't care what paperwork you have they will NOT allow access to the dying or dead persons records. You have to go specifically to the social security office/website and designate a specific person(s) who are allowed to act on your behalf. It complicated things but I was able to work around it.

I would also recommend a yearly review of all the paperwork and be sure it's up to current needs and you've included any/all changes over the past year. I got all my paperwork reviewed and updated late last year with an attorney and it was "cheap" and only a few hundred dollars - don't rely on the self done paperwork it is well worth the cost to be sure all the little issues in your area's legal requirements are covered.

There are also several articles on having a "death file" and what it should include that helped guide me in setting up my paperwork.