Ok, I can try to answer a few of your questions here since I know a decent amount about Simplex equipment myself. Regarding the central monitoring situation, it would more than likely be best to contact BOTH the fire dept. and the district’s maintenance supervisor to be safe. However, I would assume that the third party company that gained the contract with the school is more than likely the party responsible for monitoring the fire alarm system, as most systems are typically monitored by a fire alarm/security company and not the fire dept. itself. In other words, the system is typically monitored by a company who then refers any alarm events to the local fire dept. So if possible, I would try to contact someone from your school district who may know if the panel is monitored by that company. Answering your second question, if the level access codes are NOT default, the only way to restore the panel back to factory default (if I’m correct here) is through Simplex’s extremely proprietary software, which is not possible (or legal) for any enthusiast to own. Finally, to answer your third question, you ALWAYS disconnect the batteries FIRST then AC power when powering down a control panel. The same would apply for the 4009 NAC extender. Hope this helps and good luck bidding!