Banners can be mounted from walls on telescopic holders. Or they can be hung on poles that are pushed into permanent brass floor mounts. The brass mounts are a lot like electric outlet caps in the floor. Setting up seasonal banners is easy from service to service. Finding storage space for banners, seating, altar furniture, and other accessories is perhaps the most difficult part of using a multipurpose building.
Some congregations dedicate a separate room for storage.
People at First Methodist wish they had done that. They now realize they don't have nearly enough space for unused equipment. Multipurpose buildings can be wonderful places for growing congregations. But they take a lot of wisdom and planning. They also require open mindedness regarding worship space.