I can do most home maintenance stuff - electrical, most plumbing, fixtures, appliance repair, etc. I pay someone to do drywall work or painting - because I'm pretty picky and I can always see where my work falls short.

I think you'll find for finishing work practice makes perfect and is where professionals shine. You can certainly do professional quality work, but expect a learning curve and to be re-doing sections of projects that don't turn out too well. I know several homeowners who have re-done bathrooms themselves, and only one would I say turned out professional looking in quality. That guy is simply a perfectionist who spent an inordinate amount of time on the project.