If I'm parking in a dodgy area, I'll put a steering wheel lock on. I bought an universal one, and cut it down a bit to fit. Haven't got an alarm, but have a tracker. I have a battery cut off switch, but my battery is easily accessible under the bonnet so am going to remove it as it's a bit pointless. If your battery is in the back, disconnect it with the cut off switch (but make sure there is still power going to the alarm and tracker.)
