Write it and see, that is the only true way to find out. There is a famous scene in one of them Clint Eastwood films, the Good Bad & the Ugly, Tuco is lying in a bath and a guy comes in with a gun and starts talking about how much he wanted to kill Tuco, but then Tuco lifts up his gun and shoots the guy and he says " If you're going to shoot shoot, don't talk."
I just spent 2 weeks working in one...a big community centre...less of the jumble sale scene, more...
1. The reception desk and a maintenance crew. (10 people?)
2. A wholegrain type granny cafe - with an atmosphere of mentored/supported employment.
3. some fringe, homeless guys dwelling abouts the lobby, or they get themselves a meal here and a break from the other homeless guys, using the centre as a base - they overlap with the chess crowd who come here for company.
4. A nursery creche
5. Enormous hall for worship. Vicars. Big religious scene: provides financial backing/purpose, charity.
6. Politicos - community groups lobby the MP who meets them here
7. drugs, AA, Gamblers anonymous, actors
8 Rooms rented to businesses and language schools...comedian workshop on top floor, ha.
I was attacked by a seagull here, up on the roof actually. Really hot day so I brought all these - 20 teenagers - out on to the roof for some fresh air. The gull attacked my head and shitted all over me. The kids kind of loved it, un-nerved a couple. I was shocked, felt a fool fighting a bird - I'm over it now 
...better write it down, eh...atb