I've driven up Bobert's dirt-road driveway in a standard sedan ('06 Hyundai Sonata) with no problem. I wouldn't think that any Toyota, even the smallest and sportiest model, would have much less clearance than my car. The drive is fairly long and steep, and narrow enough that I wouldn't like to encounter another car coming in the other direction, but there was absolutely no danger of bottoming out, skidding off, or any such problem.

Paving may not be necessary, although I suppose that more regular maintenance will be necessary if you just-regrade the existing "farm track," as opposed to investing in pavement.

Putting down some gravel would be a compromise between regrading the dirt as-is, on the one hand, and going with asphalt or concrete on the other. Is that what "scalpings" means?