The only thing I do to winterize is to turn on the furnace and set the thermostat to the lowest setting (40, if I remember correctly) if the overnight forecast is for a low below 30. We open the doors below the sinks for air circulation and turn on the electric water heater element. Our storage has a power hookup.
We live in the Austin area and only have a dozen nights or so below freezing in a normal winter. Lows below 20 are rare. The furnace runs just enough to keep things from freezing.
The small amount of propane used is cheaper than the antifreeze, not to mention the hassle. I haven't used RV antifreeze or air blowout for many years.
If your climate is very cold, you can't get away with it. You have to winterize.
A better idea is to hook up the Airstream and go south!