Tell me if my thinking is correct: since debit card fraud is not covered by the car issuing bank, but most credit cards are (expecially American Express), then I am thinking of prepaying into my credit card instead of the checking account my debit card uses, so that even though I get a cash advance from the ATM I do not have any finance charges. Yes, I know there are transaction and/or conversion fees, but at least I won't have the finance charge and the risk.Correct thinking?

Would not prepay just use CC with no foreign fees

Travel with Debit Cards quite risky as you point out

due to unlimited liability for funds even loans

on a main account.

Always travel with my no ATM fee www.capitalone.com Visa

use it a lot best exchange rate no foreign exchange fees

most important NO significant liability.

ATM use is a cash withdrawal will acrue interest daily

always pay that off quickly when I get back or online

while traveling.

But you are correct no liability that way

AMEX is NOT widely taken would go with Visa ideally or M/C

I think the only way to know the answer to your question is to call whomever issued your card and ask if that's how it works.

Can't give you specific figures, but American Express is not as widely accepted in Mexico as Visa or MasterCard are.

Your credit card will start interest from the withdrawal date, fraud occurring on a debit card can be recovered the same way as on a credit card. Better to use a debit card on an account with a limited balance, if you're worried that much.
BTW just as much fraud going on north of the border, as down here.
Also few places here accept credit cards.

We, too, use our Capital One Visa card because it has no foriegn currency conversion charges. Just make sure the merchant puts through your charges in the local currency and that the merchant doesn't do a conversion on the bill. Also, make sure you contact the Cap One fraud department prior to travel to advise them you will be on the road. They have been known to freeze accounts with foriegn charges without prior notice from the cardholder.

We have an Schwabb ATM card that rebates fees, so that is what we use for cash. It is connected to an account with a limited amount of funds loaded in prior to travel.