First thing is to perform a energy audit to determine your wattage usage. small plug and play devices are best for this task. The one I recommend is called Kill-a Watt ( runs about $40.00). To use it is as easy as plugging it into a power outlet then plugging the appliance into the unit. Instructions are easy to understand and follow, allowing you to know what the appliance cost you to operate it.
Once your audit has been performed you can then determine how many watts your system should be. Keep in mind reducing you wattage usage is your first priority. We switched out from incandescent bulbs to led and cfl bulbs and dramatically reduced our usage. Some appliances will be unusable due to their higher amp requirements, ovens, A/C, furnace, and water heaters. Most portable configurations can't handle more than 20 amps.
Power usage management is critical to making the most out of your portable unit. How many panels, batteries, and type of inverter will depended on how well you are able to reduce and manage you power requirement. Small configurations can be easily transported if need be. The Power source 1800 from mysolarbackup.com is the Sarge's choice for plug and play units. The price is not cheap at $1600.00 but for it's ease of use it would be perfect for Preppers who are not comfortable with electronics.
As always, The Sarge is on duty!