It only takes 10 minutes to winterize once you have drained your HW tank and turned the shutoff valve. Don't burn your expensive propane to heat the trailer plus as others said 50 degrees won't be enough to protect the tanks below. With my Bullet, I don't blow out the lines, I use a $10 Camco winterizing hand pump I got on Amazon to hook up to the city water faucet, stick the hose in a gallon jug of $4 Walmart RV antifreeze and pump it through with my wife inside turning each faucet on until pink comes out starting with furthest faucet from connection ( Kitchen faucet). Then I do bathroom faucets, shower faucets, toilet flush and outside shower. . Then pour a cup down each sink and shower drain, and a few cups in the toilet drain and DONE! Total time-- about 10 minutes and 2 gal of $4 antifreeze! Why risk your expensive bullet having freeze damage for the easy task of winterizing? Then close er up and if you decide to go winter camping, either bring bottled water and use CG bathrooms and showers ( if they are operating) Otherwise if not, just winterize again when you get home.. It is such a fast and inexpensive easy task, you should not take a risk in not doing it!