The Minivan from Luang Prabang to Nong Khiaw is a bit messy. Rather than a direct minivan pickup and departure, they sent a tuk-tuk to pick us to a bus station and then distribute us to the minivans, where we have to wait until the minivan is full, and waited further for unknown reason. The minivan end up an hour late for departure. The 3 hours journey is extremely bumpy, the most bumpy journey we experienced in Laos so far.
The Nong Khiaw bus stop is 15 minutes walk away from the bridge (center of the town). The town feels pretty "deserted" with no much tourist activity seen.
We took a boat at the jetty before the bridge to Muang Ngoi, where I was told the last boat leave at 2PM. The journey is nice, many white buffaloes and wild boars are seen along the way. The 1 hour journey on wooden seat is pretty hard on the buttock.