Just my two cents, but you couldnt pay me to buy a 140k mile BMW. I'm not saying they don't last a long time, and as long as it doesnt bleed me dry, I plan on keeping my X well past that point, but you're just asking to spend gobs of money on repairs at that point in it's life.

Again, just my opinion, to each their own, but if your budget is such that the only BMW you can afford is one with 140k miles, you should probably be looking at a newer, non-luxury vehicle.