4x8 i custom built this trailer it had a 20 ft stick of 3/16 tubing to make a stronger axle it's over 3,500 lb rating extended a longer tongue made out of the same tubing and several support structures underneath the rest built out of 2x2 angle every seam welded.
2x12 treated lumber on sides can be removed for ramps every 2x4 sheet metal wood screws on every board lockable built-in lock on the tongue heavy duty chains toolbox could be removed wanted or leave it on and covers made to protect rear trailer lights
This is not a lightweight trailer by no means and the tongue being made out of 3/16 tubing makes the tongue lifting it up heavy it will not bend ever.
Originally I built the trailer for a canoe and modified it with the rails to make it more of a landscape multifunctional trailer hardly ever been on the road paint is a little faded but still like brand new