Here's something to wet your appetite,from my fast bikes magazine dated june 1993,£15k new so yes in my opinion on the price uplift in 27 years......but bricks & mortar is the only way in life for investment.
I read an article in Fast Bikes about a new MV 750-4S. Handed a fast by Ferracci guy a wad in an envelope as a deposit Finally got one two years ago.
I wasn't quite divorced when I nearly bought a Tony Scott tuned rc30 in rvf colours in a reading dealers, when I did divorce a little while later I paid 12.5 k for a 916 , f*"k it, I thought no regrets.