Unfortunately, I'm by no means an expert!
I make my decisions, financially, based on research like I laid out above.
Generally speaking, I do see today's prices as a bit lower than a few years ago. Based solely on years-old auction results compared to recent results.
I suspect this has more to do with a dwindling base of buyers than anything else. As unfortunate as it is, folks like your friends father are headed to the big gun store in the sky.
I tend to be the youngest guy at the auction house by 10 or 15 years with a large gap in the middle and a big concentration of the post-70 crowd.