Battery bank or voltage converter?

Thanks James, one more question. what is the most efficient way to wire-up 2 12v batteries in series for 24vdc but then draw only 12vdc for the inverter? im kinda confused on how to charge at 24 and draw all batteries equally at 12v. thanks again

im asking because ive gotten my dad interested in solar, and now, after loosely rigging up our newly built shed (gallery pics), he is thinking of taking the entire garage in the house off the grid(baby steps). for loads, it will most likely be limited to 4 12v lights, hopefully cf, and then to an inverter for light power tools and the sort. he found a 1.5 kw mod-sine inverter from some catalog that he's going to purchase shortly, and wants to possibly use it in this app. i think 1.5 might be overkill but he wants it just in case he needs a larger circular saw or possible space heater. okay, so a straight 12v system. a mppt controller may be out of the question for now, but definitely a possibility in any larger system in the future. as of right now, we dont have another CC or inverter, only in the smaller shed. this is just in the pre-planning stages. what did you mean by "just try to keep it under 3 series strings in parallel"?? thanks   Ian