Then expect to be the last peg in the totem pole, if your not paying the bill or are the owner, you are expected to do as your told. Yea you can't have guns in here because it might upset the daycare and by the way we are planning to house the drug addicts in your messes, that won't be a problem will it? (Seriously they tried to do that at our Cadet hall).
I've worked out of hockey rinks where despite having the "keys to the building" we were also told to avoid certain rooms due to chemical hazards. We were also told to save the zamboni if possible but were not allowed to drive it.
I've worked out of Legions where they still operated some meetings while we dealt with operations. Bar was locked however for everyone's comfort.
I've worked out of schools where boot rules had to be zealously enforced so that field wear did not damage all the refurbished floors (logging caulks and gym floors don't belong together) and certain rooms were closed off so that the soot of fires did not damage carpets. We got evicted due to school starting shortly after a week but it provided an initial ICP until such time as a incident specific camp could be set up on the outskirts of town.
So I can easily see working out of an armoury where some rooms (arms locker, comms gear) is off limits. Or some unit staff continue to access specific needs and rooms with pre-determined access worked out prior to entering the space.
What I generally need is a large enough space to set tables/chairs up, a ton of power cords, some washrooms and ideally a coffee pot. Quarters can be a tent on basically any flat surface and food can be arrange multiple ways (resturants/seperate camp set up/ etc.). Comms are done via cell phone and wifi normally, satellite uplink if remote enough.
I do however believe that this only works if its a short term need. i.e. not converting to a daycare + but a time period measured in days/weeks and is done with the understanding it allows for initial deployment with plans to change once situations stabilize. It can not be the sole location considered without footing a significant part of the bill.