What about tracking guild activity automatically if no-one from the guild walks into the guild hall then the hall gets re-possessed by the city & goes up for auction. maybe there should be a sign-in sheet & if you do not sign-in @ your hall once every 3 months then then it goes vacant until you sign in or another guild buys it.
Also a guest book would be nice so you can track guild activity...

Feal free to add to this...