From what I have read the placement of the panels in conjunction with the arc of the sun is important for getting full power from them. Also there are 2 maybe 3 different cells on the market HF has the cheapest units and are the oldest technology but they still work but have a low % of efficiency, you wont power the barn or house a few lights maybe from the batteries, and that is dependent on the battery bank size your controller and inverted sizes.
New technology is coming out every day, but in MHO unless you get a BIG tax break or can sell the power you dont use back to the power company. It is not economically feasible to those of us that have to work for every dollar we make.
No matter how hard you try to get off the grid, it aint gona happen. Some places have levied bans on solar panels others have tried to impose taxes on them, and I dont remember where it was, some place, the power company began pursuing law suits against people that were trying to go total solar on their vacation homes , where running a power line would cost you and arm and leg and maybe your first born.
Just some things to think about,,
Oh and NT has a few complete solar set up, 400 watts I think for like a couple grand, panels controller and inverted and a couple batteries,
Also you might want to make some discrete inquires about this to the local powers that be, and the power company as well,, you know,,, I have bet with a friend about solar power and I said the power company wont let them in ,,,so do I own him a case of beer or not?
Works with the local officials, and you might want to check with the state about a tax rebate,,
And go on line there are several sites where you type in your location and the orientation of the roof or panel array and they will tell you if you have it right.
All the best with you solar project
It might be a lot of fun to play with, but I cant afford a set up , I doubt if you would ever get your money out of it in our life time