Hello rollout and Welcome to the forums. You can put a gallon of the non toxic RV specific antifreeze into the holding tank. When I travel in the winter and still want to use my facilities, I have blown out the lines with a small air compressor that I carry along in the tow vehicle before departure. SO far, I have not had a problem. As in post #2 above, the safest way would be to tow with the unit winterized, for NO surprises.
Kevin with Baity the Lab/Pointer
//------AIR # 7303------\\
visit my restoration blog at: