There is a way to convert a crap 8" wheeled trailer to 13" which gets you out of wheelbarrow tires and into automotive tires but it's not really worth it in the end.
I have done it and I have moved on.....not worth the effort and the extra $ for tires, wheels, fenders etc.
You still have a thinwall frame that is too narrow for a DB in most cases.
Not recommended (no matter what AP says ).

The one I converted was never "right".....even though it looked great.
My biggest complaint was that it was too narrow and too high which made it a PITA to load the DB.
It cost me $550 and I sold it for $300 to a friend with a narrow jon boat that fit the thing much better.