Re: WINTER WORRIED
There are several areas of concern.
1) is the water hookup. This has already been addressed.
2) is the water lines in the trailer. Either they are adequately protected by the design/construction of the trailer, or they are not. If not, the trailer is not appropriate for full timing (or at least not in any freezing climate).
3) is the storage tanks. If they are enclosed and heated via your trailer heater or a separate heater, then no problem. If they are exposed, either drain them (fresh water, don't need it if you have a water hookup) or apply electric tank heater pads. Actually, the dump piping is of more concern than the tanks themselves, so again, heat tape is good.
4) is from the trailer to the dump station. Already covered.
5) is 'external' water concerns. If you have an ice maker, check it's line. Even if all the other lines are protected, this line may be small and right against the external wall, or particularly vulnerable. Any external shower should be investigated to see if it is vulnerable. These are the 2 I know of; there may be more