I try to follow account security best-practices (strong random passwords, password manager, multi-factor authentication, etc.) but I still find myself worried about potential compromises to my accounts, in particular financial accounts (e.g., banks, investments) or accounts that could lead to financial account access (e.g., email, phone). It got me thinking. For people who's net worth is on the order of $10M or $100M or $1B, what additional precautions should they take? Special arrangements with financial institutions? Payments to security specialist firms to monitor/manage all accounts?

This question is related, but the asker didn't understand basic security precautions so the answers tended to be rather basic. One of the comments points out that some rich people completely disregard their security:


  Worked for a guy once, owned a decent sized company (and a bunch of smaller ones), with a personal worth of mid-nine figures, and his password for everything was 'bob'. Three guesses what his first name was.


Which is why I'm asking what should high net worth individuals do to secure their financial account access? I'm assuming there must be something given they're a much larger target than Ye Olde Pleb.

Googling around, it seems that some financial institutions offer RSA SecurID. The obvious risk to that is still a phone call to their support team saying you lost it, but it's something.

Bonus question: How much do those extra security measures cost? I.e., at what point in my Inevitable-Rise-to-be-Richer-than-God do I seek out such precautions?

The best security measure is quite simple.  Don't use accounts that allow your money to be easily stolen via the Internet.  Happily, high-net worth individuals have used systems like this since before the Internet was a thing, and are in fact particularly likely to choose them regardless.  While banks certainly aren't perfect at protecting money from theft, historically, they do a massively better job of it than the individuals who have money to protect, high net-worth or otherwise.

First of all, when you're a billionaire, your money is not in a checking account.  Most of it, in fact, isn't liquid at all.  It's ownership of corporations, real estate, things that are difficult if not impossible to steal in any but the most convoluted ways.  

For the assets that are somewhat liquid, the vast majority of them are still going to be investments.  And there's not going to be in an E-Trade account with a web login.  They're going to be held by an investment bank that caters specifically to high net worth individuals, managed by private bankers whose job is it to know what's in your portfolio and how its performing at all times.  It simply isn't accessible to outside threat actors.  
