Re. "having to use my left hand": are you left-handed, or switching to your left for that side of your face?

If the latter, i.e. you're naturally right-handed, then I'd suggest just trying to use your right hand on that troublesome bit. I never did get around to learning to shave left-handed, and so I make use of a fair bit of contortion to get those tricky to reach spots. But it *is* totally doable with one hand. You just have to find which (admittedly weird at times) combination of reaching, stretching, and shaving works for you.