It used to be that one-man-bands had to look like this:
No more! My friend and colleague Mike, from the comfort of his apartment, played guitar, bass, percussion, and banjo for this song that he wrote (he also sung lead vocal and harmonies). It was for our class on Hebrews, so maybe you can catch some of the words of that epistle in the lyrics. Mike would prefer that someone else sang - but then he wouldn't have qualified as a one-man-band - and, I think you'll agree, it's a pretty good band.