Parapet walls are not the ideal construction in the harsh climatic Namibian environment. The constant change between hot and cold, dry and wet will ultimately lead to cracking of the plaster of parapet walls, as they are not protected by a roof against these climatic conditions.
To rectify this, remove all loose and flaking paint and apply one coat of NEO Bonding Liquid. Paint all cracks and the top of parapet walls (going 5cm over the edges both sides) with 3 coats of NEO Elastic Waterproofing. Paint 2 coats of finishing NEO PVA of choice over NEO Elastic Waterproofing when dry (recommended as the waterproofing will be protected from the sun by the paint and thus stay elastic much longer).