a tool set. screwdrivers, with square drive (robertson) phillips and flat. water pressure regulator Tire pressure guage, wrenches, torque wrench with sockets if you have alum. wheels, allen keys, elec. tape, duct tape, multimeter, utility knife, assorted screws, bolts, awning deflappers, picnic table cover and clips. That is about half of it.
25' to 100' rg 6 catv cable, w/ couplings, water & waste hose minimum the length of your unit, power cable extension cord, particularly if your power inlet is on the rear of your unit.
Assorted lumber for leveling blocks. Forget the expensive breakable plastic stackers.
Keep in mind to have one leveling jack in contact with ground in case of elec. ground fault or static.