we have industrial vacs and a local criminal seems to have keys to our service doors. apparently they are only 1-2 differenty types of keys that will fit most all servicie doors. he is comming by at night, jamming the slugbustes, then returning later to pocket the pitiful amount of change. in the meantime my customers are obviously livid about loosing the money and i am sick and tired of unjammin the slugbusters, just cant seem to every catch him. what would be best solution for greater security? thanks,