The bumpers on the trailers are well known to not be very strong and not a good weight load. These should be re-engineered and welded into the frame to be safe for almost any additional load you might want it to handle. I think the were only designed to safely hold up a single spare tire...
Check out one of these IDAHO TOTE with swivel wheels which is NOT considered a trailer but rather an attachment to the trailer. I have seen both the two wheel types and single wheel type. I would think the two wheeled attachment platform would be the best to use. Being attached to the rear of the trailer makes for a very easy back up routine with the swivel wheels...
Check with your local State DOT Safety office to get all the info how these are allowed in your home state. This of course will add to your overall trailer length...




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Roy Ken