Not that I'd swear off fixing what I could if I had unlimited funds, but I don't. So I fix things.
A few weeks ago I did the latest rebuild of the hot-water valve in the shower. It goes more than any other as it is a Price-Pfister valve with a rubber washer, gets a lot of use and is very close to the water source and hence gets more pressure despite the new pressure-reducing valve we had installed (by Philip the plumber; I know my limits, or at least I think I do).
The valve seat was OK, and the valve stem was replaced (by me) the last time I rebuilt the faucet. Despite the pressure-reducing valve, a whole lot of pressure builds up in the system when the water is off for any length of time. I might need one of those little tanks above the hot-water heater that helps even out the pressure. Or something else. I'm open to suggestion.