I've already done that, it's easy to do with lots of advantages. No brush marks or spray bloom to worry about ,even overspray isn't a worry on your property. I try to do them on country lane laybyes you can just leave your bucket there, no cleaning up at all just splash and dash as they say, runs can be a problem though the secret is to throw two bits of wood in front of the rear wheels to drive over keeps it out of the tyre treads clever eh! it's also sometimes better for the environment as i try to use green where possible. Another tip for doing underneath your camper with waxoil etc, with those hard to reach areas in mind, is as follows, pour the substance old engine oil or whatever into two good sized potholes matching your vehicle wheelbase, should be plenty around your area, (easy to spot with yellow ring round) then simply drive through at high speed for a top quality vehicle underseal.