The thread for building a small house in Thailand for under 500,000baht, ie under 50 square meters, if you reckon 10,000baht per square meter building cost your going to end up with something quite nice, ie cheap granite floors, good roof with some insulation, maybe able to get a aircon or 2 included in the price, but no gold plated taps etc.
So onto the first one, 36 square meters, 1 bedroom and 1 bathroom and kitchenette, ignore the balcony as that would be extended to a proper outdoor seating area.
Don't look so bad, only bad point is the shower area being 1 meter by 1 meter.
So post your favourite floor plans.