4.5 years ago and the gas heat is now only 10 years old as the previous owners did replace it at some point. Ditto for the water heater.

But the A/C? It's original to the house, which makes it about 25 years old at this point. Still runs, reasonable energy efficiency since we're well insulated, though certainly new would be better, but I'm reluctant to screw with it since the quality of these sort of things seems to be less now than it was 25 years ago.

Oh, and this is actually the first time I've purchased a refrigerator. Every house I've bought had one there already that worked fine. I've bought a stove once, a few washers, dryers, microwaves and one dishwasher, but this is my first ever refrigerator purchase.