The BX can do anything... if you have the time. You do need to remove all the topsoil and that could be 12 inches or more. If you don't, any drain fill you put on it will sink into mud. Then put down a drainage/compacting base. Different areas use different products. Where I am we have access to a glacial remnant called 'A' gravel. You shouldn't have to compact it the drainage fill, at least we don't. It gets pretty well compacted with the BX rolling over it time after time as you spread and level the gravel. The motor home will also compact it. Just take it easy when you first start onto it. Go on a bit and back off. Use the motor home as your compactor. Oh yes I forgot to mention. The topsoil you removed will have to go somewhere. That is another big job using just a BX. I've done it and know.