In some countries, you are not allowed to have privacy screens (especially fences) that are higher than 2 meters without getting a proper planning permission. Whether you are also required to get a planning permission of trellis on top of your privacy screens also vary with local authorities.
Although the guidelines around hedges in most countries are less strict, you will be required in many countries to keep evergreen hedges below 3 meters. Nonetheless, depending on where you live, you may have local regulations restricting how high your hedges, trees, and gardens structures should be.
In Soldiers Point, however, there are numerous small urban gardens with high fences and trellis, which means that nobody seems to worry much. However, there are cases when your neighbors may ask you to reduce the height of your privacy screens Soldiers Point fences or hedges, so you should be ready to cater for such situations as well.