I have the 30 gallon which is just to big. I should have bought the 15. I try not to fill it all the way as its just to heavy and sometimes cannot back up the TV to get near due to site restrictions. Mine has the ring that goes over the ball and wheels so I just tow it. I open the vent and cycle the dump valves, gray last before disconnect and check the weight if I cant hitch it up. Otherwise 30 gallons of kick apoy joy juice, weighs in at around 240#. Fortunately I only have to do this once or twice a year as we are conservative while dry camping and take navy showers.
