replaced one last year and was surprised at the wide range of prices out there. Using Home depot's recommended installers seemed to be the most expensive way to do it. In fact if I remember right it cost about the same as the heater and installation from the plumber I used as it did for just the heater from home depot. Or it least it was cheap enough that I didn't feel it was worth it to do myself. The plumber will also take the old one away for you.