For home use I have seen most people buy dirt in bags. A sedan or even a compact would handle carrying those. The open sides can be a benefit for sure, but I don’t know about putting cargo ‘as high as you want to,’ given that wind is a thing. And vans are pretty tall anyway!
I understand that they can have some utility on a farm or something, but the average person is not regularly transporting a ‘couple loads of dirt’ in suburbia.
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