Sadly if they want the contents of your van they will get them. I don't doubt we all harbour the same thoughts of how the low lifes should be punished, but successive governments introduced cautions, warnings, final warnings, reprimands, final reprimands and "restorative justice" to make sure that even if these wasters are caught, they hardly ever go to Court. That's why so many magistrates Courts have closed over the last 20 years.
Of course, if they go to Court, it will turn out that it's your fault for owning such expensive equipment, while the miscreant has nothing, so the Courts will impose a punishment that is not worthy of the name, like a fine that won't get paid. Contrary to some opinion, prison works, after all if they're locked up they can only steal off other dross.
As inconvenient as it is I empty my van every evening and hope that they use a torch through the tinted windows so they can see it's empty. Old step ladders and other old stuff stays in the van, but nothing with resale value.
So the tools are in the house. If they're willing to meet my dogs to get the tools, they deserve them.
I know some tradesmen have a lot more stuff and it might be impractical or next to impossible to do the same.