The value of classic cars is certainly a strange one.
My Triumph Stag for example.
I bought it in '86 14 years old as an old car, to get me to polytechnic. It certainly wasn't a minter, well used and rusty, and cost me £3,700 which was largely paid for by my student grant!
In todays money that would be 11 grand, which makes it a very expensive car to buy for a 19 year old student today, but didn't back in '86. It's actually like a student buying a tired 3200 or 4200 today to go to Uni!
After using it as a daily for 4 years and transport to my first job, I completely bare shelled it and rebuilt it over 5 years.
I can't tell you exactly how much that cost me, for, I wasn't foolish enough to add it up, but the body shell repairs and paint job was a single £5K bill. So probably £10K, this being now over 25 years ago.
So today value wise even after all that time, if I sold her (never will after 34 years and my first car), I would only possibly get my money back.
Although I still love the Stag, I wouldn’t buy one today (any car of that era) and those who do are mostly 50 years old plus or more, in the future, who will be interested in a 50 year plus old car? The interest can only decline, and thus value?
This will surely apply to newer 80's and 90's stuff too as the owners get older, more so as we move into the next automotive chapter with electric vehicles.
I therefore wouldn't recommend anyone to buy a classic vehicle as an investment.
It does make me chuckle when fellow owners of my M140i say its a classic etc. Who will be interested in one in say 10-20 years, certainly not in 2070 like my Stag relative today.