First, call the front desk asking to speak with maintenance- if there is another branch located somewhere, say you're from there, in town with some equipment they need. If they ask you who you want to speak with, ask who's currently working. When they give you the names, write down the time, date and name or commit them to memory. Also write down the receptionist's name.
Then, later that day or the following day, call back and pretend to be one of the people whose name you wrote down. Use a different voice. Say you've got a new maintenance guy starting in a couple of hours, but you couldn't wrangle up a key for him yet. Give them a fake name coordinated with fake ID you've already put together, just in case. Then go put on the maintenance uniform you sewed together the night before.
You're almost done. Make your way to the building, and talk to the receptionist who should let you through. If anyone else stops you, drop the name of the receptionist and NOT the other maintenance guys, so the stopper won't be able to unravel your loose end. Say you're an outside contractor doing some special electrical work. If they still aren't buying it, knock them unconscious with your tripod.
And that's all there is to it!
:thumbup:
(Alternatively, asking politely works 92.51% of the time, 99.99% with goodish measures of friendliness, confidence and charm thrown into the mix).