There are many procedures needed to fully de-Winterize any RV and sanitize your water lines. It seems everyone has their own way to do it. I am attaching one UTube video of many out there as a sample of one way to do it, FYI. Some things I do differently and in a different order than the video because my coach is not exactly the same and I have preferred procedures. It just gives you an idea of one approach to getting ready for camping season.
I guess that's why many folks rely on the Dealer, and many like me, prefer to do it myself, which ensures that it is done completely and safely (in my mind), and I check that there are no leaks or other problems during any part of the procedure. If you don;t use pink anti freeze it might be a little easier but the water lines should still be sanitized. Happy camping.