I use a small pump that is hooked up to the cold water feed of the washing machine. Pink RV antifreeze is pumped in from a 5 gallon bucket until it comes out the open faucets in the kitchen and bathroom. I dump 1 gallon in the washing machine and run a quick spin cycle. The hot water heater is drained. The toilet gets a gallon of the pink and is shut off at the water line valve. Shower head disconnected. I have a separate shut down system for my pond that utilizes an air compressor and a valve system. Shutting down both takes 45-60 minutes.
I run the water for 15 minutes in the spring to flush the pink RV.
I would never leave the heat on during the winter after deer season is done. It just invites trouble.