A trailer-specific plan
Start with the trailer, the equipment, and the job.
A useful winch setup is more than a winch bolted to the deck. The mounting structure, line path, fairlead, battery, circuit protection, controls, and securement all need to work together for the trailer and the loads it will handle.
Tell us the heaviest equipment you expect to load and how the trailer is normally positioned. That information shapes the mounting and power plan.