I don't see how you can compare a moon base and claiming the entire moon to be yours to the real estate business and a person buying a house to live in..
When I say you can't own the moon I mean that, in my opinion, you can't go up there slap a little flag on it and say "Hey, we landed here first. The moon is now officially the property of the USA and nobody else can share it or have it because its ours".
That and I cannot imagine how much the mortgage would be for "The Moon".
I wonder... Am I the only one that's sat around and wondered how amazing it would be to be alive... say 1000years from now, when (and if) humanity is scouring outer space? Imagine... You're sitting at home and you say "I'm bored. I'm gonna take a small flight in my ship around Saturn to relax for a bit.. I'll be home later." That's such an awesome thought to me I am jealous of those that will be alive in that time frame. Then again, I also wonder if we will even survive to that time and if it will even be as idealistic as I imagine and hope it will be.
But I do agree also.. In the future there will no doubt be huge disputes over which planetary body belongs to who, which resources belong to who, etc.