If you are looking for a space saving system that will allow you to replace 13 fixed barbells and 13 fixed EZ curl bars, try the MX80 Rapid Change Adjustable Barbell / Curl Bar System. The system comes with an EZ curl bar and a straight bar, as well as 80 pounds of weight. The weight ranges from 20 to 80 pounds, increasing in 5 pound increments.
You can easily and securely change the weight by selecting your desired weight on the dial and pressing the release button. When you are done using the bars, you can place them back in the weight rack, which is included with the system. The steel weight plates are coated in nylon, so they should last you a long time.