What kind of work does Charles do? I think it might be worth a call to an employment agency, even if it is long distance, to ask about online work. Not all jobs can be done online...

If he could get his own phone number and phone, he could be a call-in for 'customer support' - a lot of those CS people are at home, but the company number is ported to their phone for the duration of the shift. Phone companies do this, so maybe they would train him?

Again, depends on what he likes to do and is good at.