I've noticed on a few occasions with 16mm (I only collect 8mm), that the variation in price from one title to another is enormous!
Condition of print does of course, still come in to play even with Super 8mm, but nowhere near to the extent it does regarding the price fluctuations with 16mm.
It's incredible at times, it really is!
Of course there are many dupe prints and well run tv prints for 16mm so this must come into the equation no doubt?
The most expensive used sale price I've seen on S8 is around $1500, on 16mm it's run into prices well over $5000 for the highest I've personally seen.
I wouldn't have a very large collection at these prices that's for sure!!