When you're traveling in Egypt, several months into a year's trek around the world with a family of four, the last thing you want is for an ATM to eat your debit card.

That's what happened to Heather Greenwood Davis of Globetrotting Mama, and it could have spelled disaster for her nomadic expedition across the globe.

The more you travel, the more you encounter situations that require you to adapt and think quickly. And finances are no exception. Traveling abroad often means a whole different set of rules when it comes to credit card fees, currency and banking.

Here are a few of the most common money mistakes people encounter while traveling -- along with some fresh-from-the-road tips for how to avoid them in your own journeys.

Mistake No. 1: Not Preparing for Emergencies

When traveling, financial emergencies can range from theft to medical issues that require immediate attention (not to mention the frustration at not being able to find an open bank or ATM during a national holiday). When Davis lost her ATM card, she immediately got on the phone with her bank to minimize the impact of any fraudulent activity. Fortunately, she also had her husband's back-up card with her. For the rest of her trip, she was very selective about her use of ATMs.

How you can avoid it: 'Always keep the number for the information line for your bank in a separate notebook, just in case,' said Davis. 'I'd also suggest checking with your bank before leaving home about what the policy would be to get a new card to you if there's a problem.'

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Mistake No. 2: You Don't Have Enough Cash on Hand

Though you may go for several days (or even weeks) back home without dipping into your wallet for cash, don't rely too much on plastic while traveling. You never know when your card will be declined -- either due to a flagged charge from your bank or because a merchant doesn't accept your credit card. (Discover is not commonly accepted abroad, for example.)

How you can avoid it: Davis' recommendation: 'Always take at least a few notes in the local currency with you when switching countries. You never know when a bank machine you'd been counting on will be out of service and there's nothing more frustrating than being unable to do anything because you don't have the right kind of funds.'

Mistake No. 3: Not Notifying Your Credit Card Company of Your Plans

It recently happened to me -- I neglected to call my credit card company before a transatlantic cruise to Spain. A charge to one of my credit cards was flagged in the Caribbean at the first port of call, and the card was rendered useless until we reached a mainland port where I could access a phone.

How you can avoid it: It just takes a few minutes to get on the phone with your company to give them a head's up. Most companies make the process pretty painless, and it will save you a lot of hassle in the long run.

Mistake No. 4: Getting Ripped Off on Exchange Rates

Novice travelers frequently fall prey to this mistake, because converting money to local currencies sometimes puts you at the mercy of others, who might see an opportunity to make an extra buck off your American dollars.

How you can avoid it: The best thing to do is minimize the number of exchanges you do, because each time you change currency, that transaction will have fees associated with it. Experts say debit cards and credit cards typically have the best exchange rates, though many carry foreign transaction fees -- find out before you travel in order to get the best deal. The worst exchange rate you'll find are those that seem 'easiest' for tourists, such as exchanging money at hotels, according to the New York Times.

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Mistake No. 5: Missing Opportunities to Save on Gas, Airfare, Etc.

I get it -- traveling is for relaxing and not stressing out so much about saving a few bucks here and there. But with a little advanced preparation, you can enjoy your trip while minimizing the financial impact.

How you can avoid it: Here are some tips from Andrew Schrage of Money Crashers: Download a smartphone app to help you find the best places to fuel up on the road; book a hotel room with cooking facilities to cut down on your dining out bill ('You significantly increase the overall cost of your vacation by eating out three times a day,' he warns) and use a daily-deal website to whittle up to 50% off your entertainment on major tourist attractions.

The Investing Answer: put as much effort into preparing your finances for your trip as you do packing your bags. As much as possible, think through the scenarios you are likely to encounter while traveling. Call your credit card companies and banks to alert them of your plans and find about any fees you might be assessed before they show up on your statement after your trip.