I have a question about home alarm systems. The previous home owner had a full alarm system, fire, medical, and intrusion. There is no motion sensors but all the windows and doors have the sensors wired in. The key panel is operational and everything seems to be in good condition. So my question is, can this be operated/set up to audible alarm for any type of intrusion without getting setup with an alarm company. I know that a company wouldn't be notified and the fire/medical would be worthless but I am more interested in the audible intrusion part. Thanks for any help.