Do Revo not do a remap that can also immobilize the car? Maybe time to get one? 
Or park the car out on the street, that might fox the low lives!!
Personally I'd take the keys upstairs with me and let them take their chances.
Yeah agree, but won't put them under the pillow

At night we now park my partner's van behind my car, so they'd have to move that first to get to the desirable car

Like to make it as difficult as possible for them (not that we should have to)