You’re welcome,
I am not the best person to talk about Portugal. Having said that, I believe it should not be too difficult.
There are a number of well informed people like @guifig @teixeiradasilva and @tkrunning who can give you better info about Portugal than I could ever give you on their bad days.
Check out the link below for some useful info on Portugal.
In your shoes with a budget of $280k or more to spend and an American passport, I would not get or target another grade A passport. I’d look at Armenia, Turkey, Colombia, Serbia, Bulgaria, St. Kitts and St. Lucia. Portugal would be my third or forth passport. I could use property to set up residency in Serbia, Ho Chin Ming, Tblisi and Colombia all at once with this budget with the opportunity for a passport later from Serbia and Colombia in the future.
But if still big on EU, I would do Latvia instead (fixed deposit option which you can get 100% back), get the residency and if I am not mistaken, have the ability to do as much in any EU country as any golden visa holder with less stress. The only down side is the issue of language as you will encounter less native English speakers than in Portugal.
It’s all down to where makes you feel good and you are passionate about.