I have a secondary question to that. These things seem to all operate online only, without bricks and mortar. How do I assure myself that a website that I have never seen before is trustworthy enough to invest, say, 6-figure sums of money in? Are there official ratings or registers, for probity rather than performance?
You may want to check if the brokerage firm/custodian is a member of SIPC, which provides a level of insurance against misappropriation. I think all the big names are members (Vanguard, Schwab, TD Ameritrade, Fidelity, etc.)
If it's worth saying, but not worth its own post (even in Discussion), then it goes here.
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