If you are having plumbing issues with your water heater and it is more than 10 to 15 years old, Roto-Rooter recommend you replace it for a newer more energy-efficient model.
The cost for this plumbing repair and time it would take to rebuild the old water heater will probably be the same as replacing it with a new water heater. You also run the risk of the old unit failing within a few years.
Compare your old model to a newer more energy-efficient model. You may be able to conserve more heat and energy to eventually pay for the new water heater.
Also look into a tankless water heater. They do not store hot water and are extremely energy efficient. Learn more about tankless water heaters as provided by the U.S. Department of Energy.