The most important part to planning is knowing what you want. Since a good amount of time was spent not quite knowing what we wanted, the system changed quite a few times. The original intent was outlines in my project proposal available here in PDF. [project_prop.pdf 48K]
The first design used a kit for a roadside light sold by Gaiam and found in their Real Goods calalogue. It also avoided the use of an inverter by using DC lights. This design was discarded because my Dad wanted to be able to run the occasional power tool or plug in a clock radio.
The second design started with a load analysis. The addition of the power tools drove the system from 500W to 1500W and the cost from $2000 to $4000. This design was by far the most complex. We tried to save power by using a DC powered sensor to turn the inverter on and off remotely along with manual switches for the same purpose.
The third design was not done ahead of time. The third design is the one that we built. My Dad likes high quality work and since I am not real experienced with running conduit and AC lighting, he hired an electrician to do that part. That way, I got to concentrate on the appropriate technology side of the system. I installed the solar panels, batteries, and inverter and the electrician installed the AC switch and ran the conduit and romex for all the lighting. The parts kit that my Dad ordered had used the second design so even though we no longer had any DC loads, we have a DC output for use if we ever want it.