WHICH PAINT IS MOST EFFICIENT UNDER EXTREME WATER CONDITIONS, CHEAP AND DURABLE!!!?

I am doing an assignment (from Australia) about redesigning house in Devikulam, India. At the moment they are constructed using concrete, this however is not good as it gets too hot inside. Our job is to reconstrust a more efficient design. I am researching what paint would be the most cost efficient, durable and best quality under different weather conditions specifically rain.