First off I guess you will want to know if the dealer has winterized it with RV antifreeze. If you plan on using any water you first will need to de-winterize it, flush the lines so to speak.
As for your plan there are two winterizing methods one is to fill the lines with RV antifreeze and the other is to blow out the lines. These would also include bypassing the hot water heater. The short cut would be to drain the lines via the low point drains, leave the facets handles open to drain water. If your temps are in the teens I would think using a short cut is just asking for frozen lines.
Retired and never looked back