The best ways I think of are
1- Buy an extra battery, bikes one, install it in a hidden place and make its connections with the security alarm. Secondly you can also attach horn with it which begins to sound when any one removes the battery terminals (break the circuit)
2- Corolla have child locks. Engage them so that door cant be opened from inside.
3- Replace the quarter glass with metal sheet or some thick glass. I saw such glass in Pak China Buisness Forum '12. It was 30k for a room window i think or was more.
4- Use steering lock or install a chor switch.
5- Remove one spark plug cable and take it with you. I do it whenever I go to my village in Mehran