Traveller vs the World: Save/Splurge Vietnam Edition

When I was planning my trip to Hanoi, I was overwhelmed by the differing opinions from friends who have previously travelled there. Some said to just wing it and others suggested splurging on certain things. First, here's the quick breakdown of my trip: Day 1 - Depart from KLIA2 at 0630 and arrive in Hanoi at 0855. Explore Hanoi Old Quarter before taking the overnight train to Sapa Valley (Lao Cai). Day 2-3 - Trekking in Sapa Valley and then taking the overnight train back t