I absolutely think it's the key that is the key, so to speak. There is obviously a standby timer that activates when the key is not present, as I've seen it do that before. I can experiment with these things, and also with locking it from the inside.
I was under a misapprehension about the lilo, because I believed the dimensions on the packet. I thought it was close to the size of the airbed so there would be little difference between them other than in the thickness of the "mattress" but not so. I think the airbed being larger might work better because it would fit in the available space without tending to move around so much. If it's not raining tomorrow I might give it a try.
Another advantage of the airbed may be ease of inflation. Of course it takes more to inflate it than the lilo, but it has a wider opening that inflates quite easily using a hair-dryer. With VtL available, that should be possible. Of course there are pumps available to inflate lilos, but I don't happen to have one.
I am not necessarily planning to sleep in the car, as I like my home comforts, but I have in the past been close to needing to do so because there was no accommodation available, and once as a teenager actually had to do it (in a saloon car with three other people - my parents and an aunt - so we all had to sit in our seats) and it was hideous in that situation. I want to be prepared so that I can do it in comfort if need be.
I've been trying to think what the checklist should be of things to take with me. Thoughts appreciated.
Airbed or lilo
Sleeping bag
Something to raise the foot end of the airbed
Water
Collapsible bucket
Kettle (VtL adaptor needed)
Washing kit and towel
Something in the way of food for an evening snack and breakfast
Folding garden chair and picnic table
What have I forgotten?
I have occasionally thought about getting some sort of frame made to raise the boot floor, for occasions like this, so if anyone has any idea about that for the SE I'd be interested to hear about it.