You get a text from a friend: "Flights to Paris are 300 bucks!" it says. Do you a) Book now, figure it out later, b) Agonize over whether you should do it and finally go to book only to find it's sold out, or c) Hit delete — you don't need that temptation?

When it happened to me, thanks to a travel planner friend who keeps an eye on all things budget travel, my husband and I were team "a" all the way. Once the giddiness — we're going to Paris! — wore off a bit, some of the reality sunk in. We're flying out of an airport 80 miles away. It's the bare-bones of economy seating so there's no checked luggage. And sitting together? Ha! With no free seat selection, it'll be a miracle if we don't each land in middle seats on opposite sides of the plane. Now, for a $300 airfare to our favorite place on earth, those are all trade-offs we're willing to make.

But when you're under the gun to make a decision it can be tough to weigh the pros and cons. For some guidance when it comes to navigating bargain airfares, I talked with Scott Keyes of Scott's Cheap Flights, the treasure trove of cheap airfares (I actually had to unsubscribe from his deals email because it was just too much temptation!). And I chatted with Ben Mutzabaugh, Senior Aviation Editor for The Points Guy, an essential site for frequent travelers.

Cheap flights are everywhere

First, what's the deal with all these cheap airfares? After I scored our flights another friend nabbed flights to Paris for $266! Is it just me or are bargains everywhere now? “We are living in the 'golden age' of cheap flights,” Keyes confirmed. “It has never been cheaper to travel overseas.” His site shared a round trip to Amsterdam for $203 the day we spoke.

But how can they be so inexpensive? Our actual flights cost $68; the rest of the price was taxes and fees. It boils down to a few things, Keyes said. There's a lot more competition putting downward pressure on international flights; newer, smaller planes can make the ocean crossing; and fuel prices have plummeted. Besides that, those cheap coach tickets aren't really how the airlines make their money, anyway, he explained. There are all those airline branded credit cards, there's cargo, and then of course those spendy seats at the front of the plane. Basically, the plane is going anyway, so the airline just tries to recoup what they can, Keyes said, so we can thank those other revenue sources for our subsidized cheap seats.

You have to do your homework to understand the real cost

“People have to do their own homework to know when a good deal is a great deal,” Mutzabaugh said. “$300 round trip to Paris is rarely a bad deal … But if you're on airlines that are going to charge you $200 in fees that great bargain becomes just a good one or just a normal one.” (If I want to choose a seat on our American flight, and anything other than a middle, for instance, it's going to cost 60 bucks each, each way.)

When you see a fare you like, do a quick Google search, Mutzabaugh said, searching the airline and additional fees. Also, “be checking about changes and cancelability,” said Keyes. “Some fares don't allow changes even for a fee.”

Beyond that, force yourself to pause and consider the costs that are easy to overlook in the excitement of the bargain. We have to drive to another city so there's gas and parking to add to the price tag. Then there's pet care (or child care for travelers with families they're not bringing along) and even a housesitter or someone to water your plants. That all eats into the trip budget. That said, remember, Keyes said, that you have to eat anyway, whether you're buying groceries, or food at your destination.

What kind of ticket are you buying?

When these unbelievable airfares pop up, you have to act fast, but don't be rash. “The real trick is, when you see those great fares you've got to know a little about the airline and the type of fare,” Mutzabaugh said. It's not really apples to apples when you're comparing fare categories, but in general, the rock bottom fare on the big domestic carriers (American, Delta, United, and Alaskan for U.S. flights) is going to be basic economy.

These fares are how the traditional carriers go up against new budget airlines, Mutzabaugh said. “That strips out some of the things that used to be included but now you pay extra for.” Namely seat assignments and baggage, maybe even carry-on. “No matter how light we pack it's hard to go to Europe without some luggage,” he said. Changes are likely to have prohibitive penalties at this fare level, too, and you're going to be the last to board, so say goodbye to any overhead bin space.

That said, some luggage makers are stepping up with solution to the no guaranteed overhead bin space situation with pieces designed to fit under the seat in front of you. Based on this review alone I'm seriously thinking about picking up this Samsonite number as my “personal item.”

Next there's a regular coach ticket, or standard economy. “That comes with normal things you'd expect in this decade,” Mutzabaugh said. The higher price “will typically allow you to select a seat, maybe not the best, probably in the back, enable you to bring a carry-on, also get a better boarding group.” You're still going to be pressed to find overhead space, he said.

Then there are upgraded economy seats with extra legroom and perks like free drinks, and a hybrid of coach and business with even more advantages. But chances are that the shocker fare you're eyeing is the bottom of the barrel.

Should you buy cheap tickets from a booking agency?

I learned a valuable lesson with my bargain ticket. I couldn't find the same fare on the airline site directly (or anywhere), so I booked through the app Hopper. I know enough to check the flight every couple of weeks to make sure nothing has gone sideways, and everything seemed fine. Then in the course of working on this story I logged into American to apply my frequent flier number to the trip. That's when I saw the schedule change: our connecting flight to Dallas now landed after the leg to Paris took off. I followed on-screen instructions to call American reservations, where the friendly agent soon told me there was nothing she could do since I didn't book direct.

Off I went to Hopper where I started with online chat, only to find it offline. Next, I called, only to get a recording that nobody was available. As any traveler in 2019 would do, I took to Twitter (my sole reason for keeping an account), then emailed customer service. A few hours later a helpful agent responded and got us on new, earlier flights that will let us make the connection (now with a long layover and a very early drive to the airport).

That's the price we pay, though, not just for cheap airfare, but for booking through an OTA. It's worth spending a few minutes to search for an alternative, Mutzabaugh said. “Sometimes those sites get access to special fares. And those are especially the cases where the airline won't be able to help you. That is one of the risks when you see some incredible fare on one site and one site only. It doesn't mean it's too good to be true but there may be some headaches.”

“Some people enjoy the convenience of the process with [sites like] Expedia, Orbitz or Hopper,” he went on. “They can and will help you troubleshoot but there are situations when there's a schedule change the airline makes that does not push through to the travel agent site that can get lost in limbo and you show up for the flight that left an hour ago.”

The moral of this story is to keep an eye on your flights with the carrier themselves. The agent at Hopper told me with all the Boeing issues causing schedule changes it may have been the end of August before I got the notice — and while she said they've have made sure we still got to Paris, I can imagine it may not have been on the least-bad option I was able to choose.

The early booker gets the flight — but you have an emergency exit

The clock is ticking when major sales hit. “The better the deal the shorter it's going to last,” said Keyes. “When you find those really good deals it pays not to dilly-dally. It can disappear at any time.”

It's worth having an understanding with your partner ahead of time, Keyes said. I was able to reach my husband by text, who replied “book now, figure it out later,” (a key to our longevity!), but Keyes has heard of people missing out on unbelievable sales when they couldn't reach their travel partner.

It's a little disconcerting to go from having no plans for a trip to suddenly having an international escapade on the books, but “what a lot of people don't realize is they have a hidden tool in their back pocket,” said Keyes. That's the 24-hour rule — and your lifeline if you book first and think later.

As long as the flight is at least a week out, “if you book directly with the airline you automatically have 24 hours from the minute you book that you can cancel or change without any penalty,” Keyes explained. So when he sees an extraordinary deal, “What I'll do if I'm not sure, is I'll book it and I've bought myself 24 hours.” (You can read up on all the details at transportation.gov.)

Low-cost airfare may change the way we plan our vacations

The prevalence of ultra low-cost airfare could well change how we plan travel, Keyes said. He thinks most people would be happier if rather than deciding where to go and searching for flights there, “they let availability of cheap flights guide where they take vacation.”

“All of a sudden you can take three flights for the price of one,” he said. “You can see a lot more diverse and under the radar places. If you're [only] going to pick a trip once a year you're probably not inclined to go to a place that doesn't get a lot of hype.”

Even if you do only take one trip (there is still the issue of vacation time, after all), cheap flights relieve a lot of pressure. If you've dropped more than a thousand bucks just to get somewhere, “there's such an existential pressure of 'I've spent so much already,'” he said, that travelers may be reluctant to spend on the things that actually make the trip worthwhile.

“If you only spent $250 to get there,” though, “that's a lot of money left over.” Money I've got earmarked for a week full of baguettes, cheese, and wine in Paris.

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