Hi all. Time to start my story...
I've been living in Tha Sala, a small town just north of Nakhon Si Thammarat in the south, for about 8 years now. We've always had the plan to build our own house, and over the last 3 years have bought a couple of plots of land next to each other and ended up with a 30m x 20m plot in total which has cost about 1 million baht after fees and having the land built up.
It's outside from the centre of town, but realistically that's only 5 minutes away. It's on an underdeveloped soi which has 4 one-story townhouses...100 metres of grassland...big 2 story detached house on one rai...75 metes...old-style Thai house covering a rai and with more land used for crops and a 30m square lake...our land on the other side of the lake...75 metres...6 one-story townhouses. A small river winds along the back of these houses and it's about 100 metres from our land, across the Thai-style house's land. We're back from the soi by about 75 metres, but this is a designated public highway as confirmed by our lawyer, and we have a friend who knows the right people who will arrange for this to be paved when the time is right.
It is in a floodable area. During rainy season the surrounding grassland does get waterlogged in parts. In the 3 years since we've been looking closely at it, we've not had any real flooding - the river has not broken its banks and has not got very close to doing so when we've checked it after heavy rains. About 3.5 years ago we had bad floods in the area (tropical storm Nock-ten in March 2011), and the owner of the Thai-style house confirmed his house (slightly built up) was not flooded, though the land was. We've build the land up to about the same height as the land under his house, and we'll be up on 2.4 metre columns. We accept that in exceptional wet weather, that the garden may get flooded, and the surrounding land probably will get flooded.