Appliances that are still working:
Kenmore dryer - Nov 2000 - I install the "rebuild kit" (rollers, drum seal, belt, belt tensioner - about $70) when it starts the steady, small thump, thump that indicates the rubber rollers are worn (about 5-7 years - the next kit is in the cabinet above the dryer.).
Kenmore HE washer - Apr 2013
Frigidaire upright freezer - Aug 2009 - The seal at the top of the door is beginning to leak (bit of frost over several weeks) so perhaps a seal replacement or maybe a minor door adjustment. Not the most efficient freezer and it's a bit noisy but we needed a replacement in a hurry when the previous freezer died and this one was available. The noise isn't a problem because the freeezer is in the laundry room.
Bosch dishwater - Feb 2011 - ALL the Bosch units which use the same plastic housing have the same problem - the magnetic switch that knows whether the door is closed begins to be separated from the magnet as the plastic deforms. Adding a small shim above the top center of the opening resolves that but may it may need a thicker shim over time - the plastic housing will continue to deform.
LG over-the-stove microwave oven - Feb 2009
Samsung French door, bottom freezer fridge - Oct 2017
Kenmore gas range - May 2008 - I did have to put the oven door handle back on when the screws came loose (likely a factory assembly problem of the screws not being torqued correctly). Getting the door open without the handle to get the food out when the oven was at 350F was interesting ;-)
We do tend to keep things "forever": 20 years for my wife's '95 Camry, 18 years for my previous truck, 17 years for the previous riding mower but I've been a shadetree mechanic since I started repairing flat tires on my bicycle when I was in elementary school.
When a small UPS died (provides power to the internet equipment) and the manufacturer wanted $50 for the replacement AGM (lead-acid) battery (specific to the unit and not commonly available) or $100 for a new equivalent UPS, I dived into the world of newer battery technology and build a replacement using LiFePO4 cells for under $20. Am I cheap? I'd say frugal. I got an education in newer battery technology, I saved $30+ and the expected service life of the replacement battery pack is at least 5 times the life of the manufacturer's $50 battery so I've saved $50 several times in the future.