Thanks, Manlobbi! That is all good advice. Some of the countries offer the option of $X in an "bank account" to qualify for the golden visa, and if the bank account can indeed be a brokerage account holding BRK.B, that would be perfect for me. The other option is shares in "local companies" and given the largest companies on the Portugese exchange appear to have market cap ca. $16B that's a bit scary.

Also I recommend to try to increase you trust level quite a bit based on your wording in your post. I empathize that you want to be careful, but the locals on the whole will try to help you, Europe has been around for a while, and you will find the English language is normally used when reading government instructions intended for an international audience such as resident application procedures.

Yes, that's fair. I am not much concerned with the governmental parts of the process, but dealing with the local real estate system would be a huge unknown for me, and the golden visa "investment" levels are a significant fraction of my net worth, so I do feel some concern about that. N.b. I have been a renter my entire life in the US so buying property here would also be scary for me :-)