Anything can be used to chock tires. A rock, a log of wood, a concrete block. Pick something simple, and it doesn't have to cost a fortune.
About sewer totes?
1. Get the biggest one you can stow away when empty.
2. Get the biggest one you can afford.
3. Get one that is bigger than your holding tank.
4. Get one that has 4 wheels.
1. Why? When not in use, you have to store them somewhere. That is something to consider. When traveling they have to fit somewhere, either on-or-in the camper, or in the tow vehicle somewhere. Where you travel with it is up to you. But it has to be put somewhere. The bigger they are, the more space they take, which means less space for something else.
2. Why? Don't cheap on on price for a knock off brand. A well made tote will last for years and years. Mine is a Barker 32 gallon -- 4 wheels. We've had it for over 20 years and it's rolled (literally) hundreds of miles and is still in good shape.
3. Why? Because bigger than your holding tank? So you never run the risk of over filling and spilling anything on the ground. If your holding tank is 31 gallons, get at LEAST a Barker 32 gallon tank. If you get a 15 or 20, .... first you run the risk of overspilling, and second you'll have to make multiple trips to the dump station (wherever or whatever that may be.)
4. Why? If you get one that has only 2 wheels, you are having to lift one end to move it and some models.... to dump it. They are heavy when full.
3. Why? Because bigger than your holding tank? So you never run the risk of over filling and spilling anything on the ground. If your holding tank is 31 gallons, get at LEAST a Barker 32 gallon tank. If you get a 15 or 20, .... first you run the risk of overspilling, and second you'll have to make multiple trips to the dump station (wherever or whatever that may be.)