What is a Feasible Budget for Homeschooling?

I would say this: a reasonable budget that you ought to be able to follow very safely would be about 1/3 of what a private school costs. That might even be extravagant in some ways. Check in your area and figure out what private schools cost, and use 1/3 of that as a budget. I think you're going to find that to be a pretty nice focusing strategy for you. It makes your budget reasonable, but keeps it efficient.