Thanks for the suggestions everyone. A couple things below:
1. We only have one marine battery. We plan on using the fridge (propane), hot water heater (propane, for my sons baths), water pump, lights, toilet, electric awning, and possibly the stove (propane). I think that's it. We are going from Friday to Monday. Think 1 battery will last?
2. We have LED lights, it came with the trailer.
3. I'm not too sure about how the tanks will be. My wife and I will be showering at the campground showers. I have a 43 gallon fresh, and 28 for the black/gray. It's me, my wife, and 9 month old son. Estimates on if the tanks will last? What type of use?
4. When not using the hot water heat and water pump should I turn them off?
Thanks again.