My motivation to use a classic car as a daily driver was partly driven by the ability to fix the majority of issues myself and not depend on a software technician or dealer only fixes.
When I was a kid, if things broke, then either Dad fixed it, or it stayed broken. We didn't have the funds to replace. Even though I am more financially secure, I'm very similar - the washing machine packed up last month, and I was gearing up to replace. However, found a cheeky little YouTube clip, and a decent parts supplier and managed to fix for under £30.
The Harley has proved interesting, as many of the parts were 'one year only' so now obsolete. However I have tapped into a large number of US breakers and NOS providers, plus a couple of 3D printers and sticker manufacturers.
I tend to rely on 'if it was made once, it can be made again' - however I am aware of the potential cost implications. Often I can adapt parts from other cars and models to fit, but I do have a half decent workshop at the bottom of the garden.
My old Corsa got to the stage where repairs were costing more than the car was worth, and there was no pleasure in DIY as they'd crammed everything so tight, and used a bizarre array of fasteners and plastic clips that seemed to be 'single use'.
I hope Classic Car shows maintain the same amount of old timers. I've been to a few in recent times that seem to have the same stuff that you'd see in your average supermarket carpark.