I'm in the house 4yrs now (second owner, house is 7yrs old) and haven't done heater flush one (I know, my fault). I was calling a couple of plumbing companies and one of them told me sure, no problem - we can come out and do the flush, 225$ a piece. Second company told me that if it hasn't been serviced regularly it's better of not to touch it all. So i'm a bit confused now on what to do. It looks like average tank heater life is 10yrs so should i just get them replaced? what are yalls thoughts and experiences? What it would cost to replace them?