The only fee one might ever have to pay when ordering abroad from the USA is to their credit card company which may add a currency conversion fee to items purchased in foreign currencies. Using Paypal is one way to get around that.
I think Paypal too has currency conversion fees.
It appears so, but I just double-checked and the last time I placed an order with CDJapan and sent payment via Paypal in Japanese yen, I wasn't charged a conversion fee, so maybe it's only charged under certain circumstances.
I think it's bank related. PayPal is not a banking institution. It's a money transfer institution. Never keep your funds in your PayPal account. If it is hacked and stolen you are not covered under US banking laws which protects you up to $500,000. (Or something to that effect)
