Looked at a 2006 XC70- Ocean Race Edition today. 51,000 miles. The only cosmetic issue I found was a door ding (small enough that it can be sucked out) and a wheel with some scars on it. One owner, service records. Dealer is selling the car and willing to give me a nice trade in on my current vehicle. I drove it for about 20 minutes. No rattles, chugs or hiccups. The brakes are not as sharp as my 2009, but the handling and acceleration is much better.
Anything that I should be asking, considering, looking for? I want them to fold a warranty into the price so that I can have some peace of mind for the next year.

Except for the blue color and a couple of badges, it is just a plain old XC70 with a 5 cyl engine and 5 speed autobox. I can't believe people would pay extra for that version.

Getting a 1 year warranty should not be a problem at all, just make sure it covers the entire car and not just the drivetrain. Also, none of this $100 deductable every time you bring it in.

They should pay you a nice difference in price for the three year difference in age.

Check the service records. I bet the tranny was never flushed. At 77K, the first timing belt will be yours, 105K+. The Haldex oil and filter will be due soon. I hope the tires are reasonably new.