I make that decision on a case by case basis based on time, money, and whether I'll enjoy the work to do the repair. There are some jobs I enjoy and some that I don't. Since I have limited time to spend on this hobby I prefer to spend it on things I enjoy. I do the jobs I enjoy, am reasonably good at, or find challenging and farm out the other things to local mechanics that need the work. Or in some cases, buy better parts. I've found that some jobs are interesting until I prove to myself that I can do it, then I prefer to move on.
