Let's see....
By members I mean shareholders, BOI (beneficial owner information) which has to be disclosed.
There is no difference between a person and a single member company, hence the estate tax is applicable.
Please give me the name of a US Broker "that accepts non residents".
Interactive Brokers US does not accept non-residents, Charles Schwab US does not accept non-residents.︀ They will open the account for you, but it will be with one of their︁ foreign subsidiaries, like Interactive Brokers UK, or Charles Schwab international, but not US.
I suggest︂ that you contact whichever broker you want to open the account with, and you ask︃ them everything about the estate tax, or you can go to Charles Schwab website, and︄ read everything about the estate tax, all the information is there, but basically, anything above︅ $60K, will be taxed at 40%
And when you ask "how will they know if︆ the foreign company change owner?" You have to disclose the name and the country where︇ you live, so they can apply the correct withholding rate on interest & dividends through︈ the form W8-BEN (besides the estate tax, there is a withholding tax on dividends and︉ interest).
I hope that helps.