Got my Vietnamese visa, one month, whole January. Decided to move slowly, 200km at a time, stay a little and then do a next bit. Saw on a map artificial lake North-West from Bangkok, took a tourist bus to Kanchanaburi, then local bus to the lake. When we reached the first town by the lake, the driver indicated that I should go. I did not like the sight of it and indicated (nobody spoke any English) my wish to go further. Driver: (pointing finger to the window): hotel! (pointing finger to the road ahead): hotel no! I got worried, then remembered I had a hammock and a bottle of water and pointed my finger to the road ahead. During next half-an-hour of driving I could tell driver thought he had a problem on his hands. Couple of stops came and went, and when our bus took a ferry to the other side of a bay - the driver indicated that I should follow him. I did. He brought me to a floating house and spoke to the owner. The guy spoke excellent English (he worked for Americans during Vietnam war) and suggested I stay at his place tonight (it was 5pm, and at 6pm it is dark) and consider my options tomorrow. So we returned to the bus where passengers were patiently waiting, took my things and ended up staying in another floating house, without any walls, just like majority of other houses in the area. Reason - with walls its too hot inside.
He runs a little restaurant, loves animals, breeds fish, not fishing himself and nobody allowed to fish on his property (he buys fish from fishermen when he needs it), and, obviously, fish trust him.