It’s really quite simple to avoid travel pitfalls

HELPFUL HINTS: Even experienced tourists can make common mistakes that can cost hundreds of dollars

The Internet has opened a world of travel for folks around the globe. But a simple mistake can cost you big-time.

FlightNetwork.com has put together a list of common mistakes people make, some of which can cost flyers hundreds of dollars.

For example, the No. 2 thing on their list is failing to check-in with the airline 24 hours prior to departing. I sometimes forget, reasoning that I fly a certain Canadian national airline quite often and they’d probably not screw things up. But the FlightNetwork.com folks say I’m wrong, noting that schedule changes are “very, very common.”

If a schedule change happens within 24 hours, it’s the airline’s job to let you know, but that doesn’t always happen.

I’ve had significant schedule changes in the past, including a flight from Budapest to Rome that was moved from 2 p.m. to 9 a.m., with no reason stated. As FlightNetwork.com points out, it’s worth taking five minutes to call or visit your airline online to confirm flight times.

Another common mistake they cite is folks who double book flights. As we’re all aware, computers can be slow. Sometimes we see that “timeout” or “unable to process” message. If you see the message, don’t press the button to book your trip again. Despite the message, you might already have booked a flight.

And change fees can be enormous; as much as $500 or the entire cost of the ticket depending on fare rules. If you get an error message, call the airline’s customer service line to be sure the original booking didn’t go through.

Even if you don’t book twice, it’s important to realize what kind of change or cancellation fee you’re looking at when you decide to take a trip.

“These fees are determined by the airlines, so they can vary drastically,” FlightNetwork.com warns. “These fees can start anywhere from $200 and range up to the entire cost of your original flight if it’s non-refundable.”

If you change your ticket, you might have a change fee and, on top of that, any difference in fare for the new booking time or date. Talk about a double whammy.

Another mistake they sometimes see is people not realizing they need a visa to enter (or transit through) a particular country.

Failing to have proper documents might mean you’re denied boarding at the gate, and you might need to cancel your flight or change it (and thus potentially incur more charges). So be sure to check early on what’s needed to visit a particular country and check again before you go in case something has changed.

Finally, be mindful of your passport expiry date. Be sure it’s current.

Also, be aware that countries often insist that you have a passport that won’t expire within a prescribed time of your arrival, often four or even six months ahead.

Which means you could be denied entry to a country for a trip in August if your passport expires in November or even the following February.