I found one area also near the gym where the slum shacks are built right next to or even overhanging a smelly canal (Klong Toey canal?). The shacks were basically clapboard single rooms that you could see though by looking at the cracks between the boards. The smell from the canal was strong, with garbage floating by on the dark green/black polluted water.
I walked a length of maybe 30 homes, but photographing their will be difficult from a tech point of view, there is very little room for tripods and in many places very limited light. I think what I will do is travel back there with Banarama 4x5 (Polaroid conversion camera) when I finally get my bag from China airlines, I can use the Banarama handheld with flash in these tight shooting locations. I want to get right in close to these people and hopefully understand a bit about their lives, if I can photograph them right in their homes with all their belongings near by that should lead to a more complete story of who they are.
Wish I had the 90mm Razzle now, oh well will have to make do with the 135mm Banarama.