I honestly can't remember about the transaction getting cash back going into the Beetle around 1970, I know at the time it was considered very sporty but the word future classic was never at play at the time.
However, your post I consider excellent, makes me feel lot's better when I look at your angle about investment along with thinking cost of upkeep that would have occured through the years.
Hey, you mentioned Insurance " funny " I found last year in old files an Insurance bill for the Jag,,, " ready " $69. for the year,,,lol