For whatever reason, I can't seem to reply to your original post. You were looking for shower locations for a group of 80-100 on the west side (or Twinsburg near 480) where you can bring your own food...
Some to check out that aren't 'community centers' per se, would include:
Women's Club Pavilion in Lakewood, St. Clarence (can supply your own food for showers, but not receptions, IIRC), Lake Erie Nature & Science Center in Bay Village, and Bain Cabin in Fairview Park (no alcohol though). If Berea would be ok, the Berea Historical Society rents their space for gatherings, but I don't know how large of an area they have.
The Cleveland Metroparks also has facilities you can rent that are enclosed shelters, if that might be an option. You can serve alcohol if you obtain the proper permits (beer and wine only). Look into Green Lodge (near Berea, IIRC) in Mill Stream Run Reservation. Albion Woods is enclosed, too, but is near Strongsville/N.Royalton.
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