Best way to get euros

Why don't you do what you always do....to the Portugal, go to a bank, and get euros.

I don't understand why you were limited to 200 euros and charge such a high fee. Where was this?

I have noticed a huge increase in foreign transaction fees in recent years and don’t know why. But, I can answer the €200 euro thing. The Multibanco’s are set for only 200 at a time. But you can immediately withdraw another 200 for your 400 in a day.

You likely are accepting DCC. When asked, indicate to do the transaction in euros and decline any conversion.

Second, you should need very little cash simply use your credit card (and decline DCC or indicate "EUR" when asked if USD or EUR)

Search this forum. There was a long post a while back with lots of info, but to copy here the key info:
There are many ATM machines all over Portugal with a sign of Euronet. Avoid them like a plague. They not only have huge fees, they also give you very bad FX rate (having to pay total of 22 euro to withdraw 100 Euro is not uncommon). Look for ATM that have MB (Multibanco) sign. They seem rare but there are plenty. You can use Google Maps to find one near you.

I have seen the advice to use Multibanco on several sites....

There are many ATM machines all over Portugal with a sign of Euronet. Avoid them like a plague. They not only have huge fees, they also give you very bad FX rate

I typically do not use Euronet ATMs (But have, and I did in Spain this month), but the statement above is a bit misleading. Typically the use fee is no more than other bank ATMs that charge a fee, and sometimes that fee is limited by the country, unless you choose additional services (like checking your balance). Also different ATMs do not charge different exchange rates, your bank, and the network it uses determines the exchange rate (About 1% almost universally for US Banks). You only need to worry about exchange rates if you choose DCC, then you are not doing an ATM transaction, but an exchange transaction. You will encounter DCC at about any ATM, including bank ATMs, and you always have the option to decline, as you do at Euronet ATMs.

We start every international trip with a visit to our local AAA office for currency exchange. It may not be as cheap as paying with a credit card, but we will arrive at our destination with some local currency in our pockets and avoid the search for a bank card compatable machine until we are refreshed after our long haul flight.