Possums live in tree hollows at least 16m from the ground and they can climb anything. I have 1m tall fences around the main garden with two strands of electric fence wire around most of it and a single strand on the rest.
There are at least 16 roses in this garden but you can't see them because they are just sticks now. The white strands are electric fence. The electrical insulators on the fence posts are at the moment just decorative but I can string another wire on top quickly if I need to. The stakes in the centre garden are for the dahlias I planted today. The house is actually barn red but the morning sun has skewed the colour.
The rose border has a much lower fence with just one strand of electric. I can step over this one but it is tall enough to keep the wallabies out. Our wallabies are only knee-high and they don't jump high like other kangaroos do so shorter fences are fine for them.
The small front garden has a very short fence that keeps wallabies out. They nibble everything that grows through the wire so they keep it tidy. The bowls are for the duck.