How cold is to cold

Besides burning a lot of propane you should be fine. If you have an outside shower, open the door and stuff some insulation in it, Leave any doors open that access water lines.

We've spent many nights in our older coach in temps as low as -4 deg F both in comfort and without any significant pipes freezing.

We have camped out in temperatures like you describe, no problem at all. Disconect the water line and drain it.
My dealer told me to worry only if the temp drop 10 below freezing for more than three days. Haven't run into any frozen pipes yet.

A lot of people here will strongly disagree. Your choice.
Winter started here last October and it's still here, we know what cold is.

I had a look at Reno weather and the next two weeks might have only one or two degrees of freezing. If you are living in it while you are there.. you will be fine.

The most sensitive spots are usually outside showers, and dump valves.