As usual, Jefe_4X4 makes sensible sense. One you can always trust to tell you the truth and channel you to someone when he does not. The audit is the best way to go and there are some places that can show you how this is done. But here is what you can do, do it in phases. Start out with a reasonable rate of watts and battery. Typical in our TC world is 100 to 150 watts. Just like Goldilocks, too much, too little, just right. No one can tell YOU what you need from their own experience. If they do, run away. But what you should do is start your system with the chance you can expand. Don't use just enough wire, charge controler or battery bank. Plan for that just extra more. Charge controllers is usually where most make their first error in getting just enough and then through use find that they need to replace it. Also, if you are going to start with one panel, buy two. Often it is cheaper to buy two and park one in the garage while you test what you have will meet your needs. Also be aware once you get into the solar conveyor you will find new possiblities opening up for you in staying "Gone" longer and going into more new areas you might otherwise have avoided.
Also, we all have skill sets different from another. Don't hesitate to allow someone else do the work for you. In this way you won't have the mental block of doing something you are not comfortable with, damage the expensive equipment while learning, or as my dad would say: "spend your free time doing something you enjoy doing and paying someone else to do what they do best." Often times you will get out and start using the item faster by doing this way. There are many here that will encourage you to do it, to the point of being annoying, but if you know someone to help, while supplying pizza and beer, do it that way too. But the whole solar thing can be and is intimidating.
By all means, have fun and for me, solar was a life changing experience and might very well be, for you too.
b