does it have electric brakes ? if so wire up the trailer plug so when plugged into tug it goes directly to auxiliary and locks the brakes on, another deterrent that may stop or slow them down.
Now that's a champion idea.... ie: the crooks have to literally drag 1.5tns+ down the road - as the electric brakes are locked on....
I am also getting a Purple Line Caravan Mover installed on mine - (long story why exactly)... and was further thinking of "drilling" the driving motors onto the van's wheels.... (These things work by applying pressure from a dc motor to the van's tyres - this is done by a 18vt cordless drill and socket).....
The thing about leaving the stress of theft to an insurance claim is 2 fold imo...
(1)
Insurers such as CIL wipe you from having any cover for any of your aftermarket goodies - (the fridge; the slide; TV; satellite; BMS; Media Systems; Air Con; Hot Water; Diesel heating; more spare wheels; the Weber; extra batteries); ...basically EVERYTHING you have spent your hard-earned on - that was not supplied from the get go -- by the van manufacturer...
(2)
Many of us spend sometimes hundreds of hours (and more) - doing customizations to our rigs - which will not typically be covered by insurance....