Barbell holders: You can mount these holders to a wall or power rack for vertical or horizontal barbell storage. Some companies make bases with slots that you vertically slide your barbell into.

VAIIO Single Olympic Barbell Hanger,Garage Gym Bar Wall Rack,Vertical Barbell Mount Rack,Black Powder Coated,Space Saving Commercial or Home Gym Accessory,Holds Under 33mm Bar Size (Black) ...