Firstly, check with the dealer, or in the manual, to see if the keyless entry system can be disabled. On some models, this is a simple case of double pressing the lock button on the keyfob. Alternatively, it's a pricy solution, but we'd recommend the Autowatch Ghost Immobiliser. It uses the buttons in your vehicle, like those on the steering wheel, doors and centre console, to allow you to make a unique PIN sequence that must be entered in order to start the car. There's also an iPhone app that connects to your vehicle and allows you to get in and drive without having to enter the PIN.

Faraday bags are also a good preventative measure, but they aren't foolproof. They work by blocking electromagnetic fields. This stops radio frequencies from being amplified, all you have to do is put your key in the little bag. We recommend this one (amzn.to/2WzCkVi) - which we've reviewed here: kit.honestjohn.co.uk/reviews/review-monojoy-keyles.../