Water heaters; supposedly, if you replace the anode rods every 5 years, most water heaters would last the lifetime of the house, versus many replace the whole unit in 10 years.
The lifetime of a house is measured in centuries. Perhaps you mean the lifetime of the person who installed the water heater?
Perhaps a better measure is the life of the plumbing system, where pvc, copper have 30-50 year life expectations.
1. You need a specific and large socket wrench. (A big adjustable wrench wouldn’t work because the head was recessed.)
2. Mine was really stuck in there, so it took a lot of torque to get it loose. Had to get someone else to hold the water heater in place while I pulled on the wrench.
3. My water heater was up in the attic underneath the angled roof, and there wasn’t enough clearance to get the new one in. Got kind of sketchy tilting the water heater over so I could get it inserted.
I'm starting to think this is the real reason I pay people to fix things for me (if I don't do it myself). YouTube makes most fixable things pretty easy. It's the climbing over/under the house, getting in hard to reach places, etc... that makes a repair a pain.
The claims of extending the life of the heater indefinitely are dubious. There are also 2 heating elements that can burn out and 2 mechanical thermostats that can fail. Cheap parts, but the heating elements can become fused into the body of the heater from rust/corrosion.
In my opinion, tank water heaters are one of those things where tank failure can lead to catastrophic damage: you have 40+ gallons of water that can dump out, and then full water pressure behind it. You have no way of identifying the condition of the tank from the outside; it could fail suddenly. Basic electric models aren't particularly expensive, either (~$600.) It's generally accepted that 15 years of life is a good run. It's not worth the risk/expense of a leaking tank to squeeze another few years out, especially if it's in an area where even a small leak could cost thousands in damage.