When you pink, make sure you get all the lines. The one that seemed to get past me was the branch from the city inlet.
Our new Sunseeker has a suction tap for winterizing; this was the first year I'd used it. Sweet! However, I still poured some antifreeze into the holding tank and pulled some of it through the lines to ensure all pipes are protected. Not only that, we are on well water, and it will grow if left too long.
I left a third of a tank of well water in our pop-top truck camper many years ago, I had a devil of a time clearing that out of the tank. Fortunately, I could easily remove that tank.
Don't forget the toilet, and to pour a little more down each p-trap.
Oh, and those drain lines with the cap on the end... wish our new one had inside valves to the drain lines.
Likewise, I collect it for next year too, but after a couple-three years, the stuff gets pretty well diluted from the existing water.
All I need is one gallon, and that's all I needed on the Four Winds as well.