Best Towable Waste Water Tote for Beach Camping

I used a 30 gallon plastic drum ($10 surplus) cradled in an inverted cut-down shipping pallet (free). Gray water transfer was by a sewer cap with a garden hose nipple, some old garden hose, and Harbor Freight 12V marine pump.
This years mods will be a macerator pump and converting the barrel for a 1-1/2" RV dump valve. The dump hose will be a piece of 1-1/2" sump pump discharge hose.