If you’ve booked a summer vacation, we hope you planned carefully, saved up enough money to pay for the whole trip and are now looking forward to leaving your cares behind. But what happens when you’re actually away, and your brain enters vacation mode? It’s so easy to upgrade, add excursions and room-charge your way to a huge credit card bill that you weren’t planning for, and that sum can end up on your credit card for the next year (or longer). So we’ve come up with a guide to keeping vacation spending in check so that you can still enjoy yourself without paying for it (with interest!) in the months that follow. See the full story on our sister site, Living on the Cheap.