Some days you're the Dog and other days you're the Fire Hydrant..what is it today?
Get one of those bar code systems. Instead of a key they use a card. You see them all of the time in hotels, companies, parking gates. They record the comings and goings of people. You can also program them to simply not open the door to certain people, at certain times, etc etc
It should be standard. Best to read the package for the new smoke alarm and determine if it is a two wire detector. If you are unsure a battery operated one will also work there. All in all, unless connected to an alarm system, smoke detectors are fairly standard that way in wiring. Just read the box, and if unsure, ask for help.
