For 2018, I've decided to travel to the Scandinavian countries and revisited Amsterdam. I've been to Helsinki and Stockholm before but on a business trip which limits me to explore these places.
Since its a DIY trip/travel, bookings of flights, hotels, trains, and tours were done online earlier. Flight tickets KUL-HEL-AMS-KUL (Qatar Airways) were booked in June 2017. Whereas tickets HEL-ARL (SAS) and BGO-AMS (KLM) were booked in October 2017. All hotels were booked online using booking.com and the hotel site. Train tickets from Stockholm-Goteborg, Goteborg-Oslo, and Oslo-Bergen were booked online in December 2017 and January 2018 respectively.
Again for this trip, booked portable wifi (Samurai) from Visondata.
Even though Sweden and Norway use Swedish Krona and Norwegian Krone, I just exchange to Euros only because both countries are going cashless especially Sweden.