HMMMMMMMMMMMMMMMM, this is a tough one!
ive thought about this before.
"""the whole problem is you just cant predict the future!"""
i know one thing hindsight is 20-20!!!!!!

another thing for sure is the GOOD stuff is always the GOOD stuff & always was GOOD & always will be!
A 70 chevelle SS was hot right away & still goin strong! a wayne 60 was always hot & still is etc... a 57 chev hardtop, a 32 ford coupe was a hot item new & hotter than ever yet today! etc..... --- ive even seen certain neat lookin cereal boxes sell high!?????! --------
when i drive an SS chevelle to work & kids ride theyre bikes in to use the pop machine from age 6-16 they say hey thats a SS chevelle i want one of those someday. if a teen drives in in a souped up V-tec honda he looks at that chevelle & says id really like to own one of those someday so i think the future holds good for that item!

i see this young guy buying bicycles that were THE HOT STUFF when he was younger & couldnt afford to get one, he chases after some bikes that arent even that old yet when the owner gets his drivers license hes there buying the guys 3-4-5 year old bike for nothing, he says im getting ahead of the game right now. only after the "HOT" desireables! hes even bought a few new bicycles that he thinks will be the good investments.

its hard to predict the future but the desireable stuff usually seems to carry right on through!