I would predict $25,000 per year could be made without answering any emails or doing anything Then it might be a better value for you to keep the business (whi

I would predict $25,000 per year could be made without answering any emails or doing anything Then it might be a better value for you to keep the business (while putting little to no effort into it) and consider the $25k/yr an annuity of sorts. In four years you've got a hundred grand, which should offset the grad school expenses nicely.