My heavy duty dual axle Gravely hauler. I u-bolted two 3/4" cold rolled steel rods to the frame of an old 48"x30" steel cart, then I picked up 4 wheels from Tractor supply on sale for $9.99 ea and attached them with shaft collars. The wheels have some light duty bearings in them so we'll see how long they hold up, but for $10 complete with tubes & tires I guess you can't go too wrong. The heigth of the trailer just happened to be the same as my car ramps so I did'nt have to build ramps and they fit perfect on top of the MA-210 snowblower.
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https://www.youtube.com/watch?v=nIIvlcw8GiE