I agree w/fl_buggy. You probably won't know what you want until you experience it yourself. What's seemingly good for someone else's needs may not work for you. Get a kit or better yet a decent used buggy. (probably a "lost interest" buggy might be a good idea) and learn (to modify) it before you throw a lot of money at a rail only to find out it is not you.
When I got into what I do I did not have a clue other than I had a Honda Pilot. I looked at a lot of rails, rail kits, glass buggies and passed on a couple of good deals in the process. I ended up with a buggy but it wasn't until after I had ridden in a rail and driven one about 100' that I found out that I got motion sick in a rail but not the buggy.
Make a plan and stick to it as best as you can. Get it running, use it and then make mods for a while until you are sure of just what you think you want... at that time. Then, after you learn how to fix and weld (if you don't know how) and are sure of what you want... at that time then start on your dream toy. I am sure you will end up modifying it too.
Lee