How hard was it to open a bank account and can you use any bank?

You cannot use any bank for this purpose. You must use what's called a custodial bank, and your lawyer will act on your behalf to open the account. First, you'll need to obtain your NIF number, which is similar to a US social security number and is what all your financial operations run through. The process typically takes about two weeks maximum. The custodial bank holds your investment shares so the Portuguese government can verify that you're still invested in the country. There are several good custodial bank options available. Making the process personal helps ensure smooth interactions with the bank. It's worth noting that if you're not applying for the Golden Visa but just investing, the process can be slightly different.