Are you sure Linux is even a great option for someone who is computer illiterate? I'm not that familiar with Macs these days, but generally I think MacOS is pretty good for people who just like doing their work, and don't have an interest in technology. It might be quite a leap to go from MacOS to Linux. I know Ubuntu is pretty good. I use Xubuntu at home, which is also fine, but I feel a little less well documented than Ubuntu. I think it would at least be worth looking into MacOS software at the same time. I think most good accounting packages have demo versions that your friend could try first. He/she may ind it worth spending some money if it provides better usability/productivity.
If you're going to settup the system for the friend anyway, maybe do a dual boot, so both paths could be esily evaluated.
