I laid 4 coats of battle ship gray porch paint with grit in it on the floor and ramp door of my 7x14 enclosed trailer, and 4 coats of white porch paint on the walls. I sealed all the floor joints before painting.
Pics below have 3 seasons on the paint.
On the walls I placed 5’ sections of etrack on the walls at 2.5’ and at 5’ from the floor on the entire perimeter excluding the rear door. On the floor I mounted etrack 4’ apart centered for the length of the trailer floor.
I have quite a bit of coin into the etrack, but the trailer can haul and move anything.
The floor paint has held up really well after three years. I simply hose out the trailer periodically.