Burglary protection - Upgrade windows from WK2 to WK3 - Alarm system?

I'm with Grym on this. The lockable handles hardly bring any benefit. The constructed scenario with fire is about as unlikely as the statement that the lock prevents a break-in.

Motion detector plus light in the garden, several times per night, is extremely annoying. And do you want to check your cameras or your phone every time you hear a noise? That drives you crazy. Besides, most break-ins happen when you're not at home. The neighbors ignore the light anyway after it bothered them for the first two weeks. Then there's the issue of light pollution. I think one should be sparing with outdoor lights. If my neighbor installed 200-watt LEDs that go on almost every night, I would immediately issue a warning.

The fact is that olives with snap fasteners stop burglars. This is, alongside mushroom head against prying and laminated safety glass against smashing, the third meaningful measure against drilling through and opening with wire.

What is the use of the press-stud olive?

We have had lockable window handles here for 15 years and have never lost the keys. We don’t keep them in one central place either, but in different spots around the house. As far as I know, there are also drill-resistant handles, I still need to inquire about that, I also have to choose the windows soon. We also have a very watchful dog and a dog warning sign on the garden fence, which might help as well.

Best regards
Sabine

Snap-fit olives achieve this by not being able to be bent from the outside with a wire.

You already know my opinion on this from the other thread, so I'll save myself the statistics and probabilities.

But I repeat that I am also thinking of 2-3 cameras. Why? I have some; the neighbor probably doesn't. So better at his place than at mine. Selfish, but what can you do.
If the gentlemen are already breaking triple-pane glass and therefore don't care about any deterrence, and the loud noise doesn't bother them either, all is lost anyway.
Check the household insurance!