A few years ago Matt stopped at a cash machine in Split, Croatia at the end of a long afternoon. The machine asked him the question every foreign machine asks. Local currency for a small fee, or your own dollars with no fee at all.

He picked no fee. Of course he did. Anyone would. Nobody stands at a cash machine after a long day and thinks the free one is the trap.

We took out 2,000 Kuna. That withdrawal cost us $340.15. Paying the little fee he was so pleased to avoid would have cost $317.42. Twenty-three dollars, on one trip to the cash machine, and nothing on the receipt to show it. I only found out days later, looking at our account.

That’s how travel money actually goes. Almost nobody loses it in one big obvious mistake. You lose it slowly, a few dollars at a time, at cash machines and card readers and exchange counters and booking sites, on charges built to look like the smart choice in the moment.

I’m Lisa. Matt and I have traveled full time for nearly a decade, carry-on only, through close to 100 countries. We have made most of these mistakes ourselves, and some of them more than once. We left Namibia with a small pile of cash that should have come back to us as about $140 and got $105 for it. I almost booked us into the wrong city to save forty dollars on a flight.

None of it is complicated once you know where to look. So I wrote all of it down.

The Price of Not Knowing walks through a trip in the order you actually take one. Booking the flight. Booking the room. The evening of setup before you go. The arrivals hall. Paying for things day after day on the ground. The tours and the extras once you’re there.

At every stop, what gets left out of the price, what it usually costs, and exactly what to do about it.

HERE’S WHAT’S INSIDE:

• Why the cheapest fare on the screen is so often the priciest

• What the room rate leaves out, and what it comes to over a week

• The one evening at home that ends a whole category of cost for good

• The one toll that cost us over $230, and the question we ask every time we rent a car now

• The phone plan that can cost less than two days of your carrier’s international pass

• The insurance box at checkout I never tick, and what I buy instead

• The word that should always make you slow down, and what it hides

• Which cash machine to use, and how much to take out of it

• Getting into town from the airport without paying the tired-traveler price

• The ride app locals use, which is almost never the one on your phone

• What your credit card already covers, before someone sells it to you twice

• Booking tours and tickets without paying the middleman’s cut

• The line on a restaurant bill that means you’ve already left the tip

• The tax refund most travelers are owed and never claim

Plus two grab-and-go checklists. One for the evening before you go, one to keep on your phone while you’re there.

Want to make sure you get the discounted price?

The ebook goes live later this week at $7, and after three days it goes to $9. Put your name down now and I'll email you the moment it's out, so you don't have to watch for it. First to know, first in line.

When it drops it’s an instant digital download. No shipping and no waiting. It’s yours to read the moment you grab it, on your Kindle or as a PDF on any device.