How much land would it take?

We do all of that on 10.5 acres. Well, I don't have the big garden yet - but plan to next year. Still learning skills. And we don't have kids. Human ones, anyway.

The cows do not blong to us -- we are boarding them - so we do not have to pay for their feed. They (2 of them) are doing fine on 3 acres with very little grain now. If they are still here in the winter, I suspect the hay bill will be pretty high for the owners.

We have a pretty big part of the acreage unused right now- so if you find a place with good soil/rainfall, I would guess you could do it on 5-6, even.