Not sure about the cost of a rig. Iwould think the most important part would be the experienced crew to run the rig. I know that when I hire heavey equipment I consider the operator to be far more important than the actual piece of equipment. I will put up with a smaller/older machine in order to get the right person. I think all capable drilling rig operators would be currently employed at this time and it would be very difficult to purchase our own rig and then staff it.
just my 2 cents, Kent