Back to the Future
19 million budget
Prints and Advertising Budget $12,000,000
As a franchise (all three together WW) $959,570,411
This type of thing still happens these days, more often than I thought!
Here are the other two as well.
Back to the Future 2
Budget of 40 million
Back to the future 3
40 million budget
From 1991-1993 there was an animated cartoon
You can buy it for 3.99 on Amazon instant video
So I could not find the DVD sales, but that has been a huge thing for Universal. Then add in the games and other merchandise as well! Hope that was good!