The furthest I've gone with DIY on cars is to replace a headlamp bulb or the odd blown fuse.
I used to service my own car years and years ago but they were much simpler then. You could get at the engine and remove service items (filters etc.) without having to wade through tons of plastic covers and wiring connectors.
You could also fiddle with fuel mixture on carb fed motors and play with ignition timing using just one spanner!
I have a good understanding of mechanics but don't have the patience or ability to do things properly so I leave it to the pros now.
I'd attempt to do a lot to mine. Maybe not a full body respray. But you cant trust other people to do your mods for you, best do it yourself, if you break something, you know where you have went wrong and can learn from it.