Putting keys in micro waves etc isnt stopping the people who steal motors taking yours if they want it.
Unless you have a ghost immobiliser on the vehicle. If they really want it, then there taking it. Regardless if your keys are in a microwave or not.
Someone i know had 2 cars taken and they asked the police what they could do to stop it. And there reply was, nothing really. If they really want it then its gone.
They advised putting a beware of dog sign on the house. Because if they think there going to alert a barking dog. Then there not going to chance it.
Its not the local ned your dealing with. Its high end organised crime, there not daft wee joy riders.