Most suburban security is a combination of hardware and circumstance: a lock, plus the fact that somebody is usually home, a car is in the drive, and a neighbour might look out. In Kommetjie, for most of every week, only the first of those is present. That does not call for anything dramatic, but it does mean the hardware has to be genuinely adequate rather than merely present.
In practice that means the entrance doors and the store deserve locks that resist rather than deter, fixings that go into masonry, and — on anything exposed — components that will survive salt and driven sand together. That combination is harsher than salt alone, because sand acts as an abrasive while the salt corrodes, and hardware chosen for an inland suburb has a short life here.
The other point is about the boundary. Where a plot backs onto dunes, bush or open ground, that side is unlit, unoccupied and unwatched permanently rather than just at night. A gate that cannot be operated from outside and a rear door properly anchored are the two items worth doing, and they cover most of what the position actually creates.