What I do: assume I can use my Taiwan ATM card and visa card, but have some backup: American dollars and/ or American traveler’s checks, as well as my Canadian ATM card and Canadian visa card. I have never bothered to get hold of cash in the local currency before going to a country, and have almost always been able to use my ATM card at the arrival airport.
In India a few years ago I had to use the backup, but otherwise I’ve been fine and have always just taken money out of my Taiwan account.
Confirm and re-confirm that you can indeed use your Taiwan bank card overseas. I’ve had banks mistakenly believe I could use their card overseas.
Make sure you tell your bank (and your credit card company) where you’re going, and for how long. The card may be canceled if it’s suddenly used in a surprising location.
For reference: I can use my Fubon bank card overseas, as well as Land Bank I think; the Post Office bank account can’t be used that way. Taixin refused to give me a card I could use outside of Taiwan.
I always have $50-100 US in traveler’s checks anyway, as backup more than anything else. And it’s a good idea to have a few American $20 bills around, as well as a few one dollar bills.
Tip: always keep a separate pouch somewhere deep in your backpack, with a photocopy of your passport, a second credit card if you’ve got one, and some American money, whether cash or traveler’s check. Plus photocopies of bank cards and credit cards, to make reporting theft easier.
(I suppose this tip is a little late now. Ah well - it may come in useful for others.)