We built our own trailer after several years of hauling with a Tri-quest we copied theirs and did some upgrades. 6 D-rings and 4 strap ratchets from a flat bed truck trailer with chain welded to them For easy tie down of a car or machinery. The last picture shows the ratchet in the front . After having them on the tri-quest for may years we had to get them for this build. One d-ring in the middle in the back . One in the middle in the front and 4 down each side. The one in the front is used with a snatch block.
Our Deck overs have Rails and pockets down the side. We also built our own dump trailer.
One thing I can tell you is you can never have to many tie downs.