The basic simple set up would be solar panel(s), charge controller and battery(s) to store the energy and an inverter.  The first thing you need to determine is what your energy use will be.  Typically the overhead lights, the water pump, the CO and LP detectors and the heater fan operate off 12V power.  Also your refrigerator my run on 12V but you should not run it on 12V while setup.  if you do not have shore power then operate on propane.  If you have an air conditioner that you must use you will not be able to operate it off a simple solar power system.  Since the camper is on your own property it might be a wiser decision to purchase a generator of 3000 watts or more that you can operate all items in your camper including the air conditioner.

To simply maintain a charge between trips a 1.5 wattt solar panel should be sufficient assuming your battery was fully charged during travel.  To recharge a depleted battery a 15 watt panel would be a better choice with either a built in charge controller or a stand alone. A 15 watt panel would provide app. 7.5 amps during an 8 hour sunshine event.  This should recharge the typical battery in 4-7 days.  It might be best to remove the battery when parking your camper and taking it to your house and charging it there using a standard battery charger. 

The cheapest way would be just to take the battery off and bring it and charge at the house/shed.  Just remember which wire is you + and - when re-hooking up.