I'm pretty proud of how good I've gotten at bike repair over the past few years, just from the time I've invested in fixing my own bike as it has issues and building a new bike from scratch. It's gotten to the point where for several minor issues, I can notice the problem, diagnose it, and fix it (replace a brake cable, replace the chain, adjust brakes, ... few other things).
Still a long way to go, but it feels so good to be able to just handle most things myself.
I recently had to take a wheel to a mechanic to get it trued. Turns out the rim was bent, so I had to get a new wheel anyway. Overall, it was well worth the $15 I paid in truing to get it temporarily fixed, and have the knowledge that I'd need to get a new rim! Someday maybe I'll get to the level of experience and equipment needed to true wheels, but it's just not worth it for me right now.