I think all of your questions would have been answered after reading this forum for 6-7 years.
I got on here and read all the threads I could for maybe a couple months before buying my first one.
To save you some time since you have already located a potential rig, you should start reading as all of these subjects are probably discussed almost daily on the forum.
I really mean this as trying to help you. Less posting questions and more reading will educate you a lot faster.
Good luck on your deal.