1948 Leaf authentic or fake?

[steve B]

Many things are less "rare" than they were before the internet.
Ebay helped show just how much there is of some stuff.

More expensive cards have usually followed a cycle of availability.
It's being bought occasionally at a decent and slowly increasing price.
It's bought at fairly high prices in spurts based around publicity.
Then the supply dries up for a while, and it eventually gets back to occasional sales.
Once a "big" sale happens, and these days big is actually a lot of money, many of the people who have held onto theirs for years decide to sell.

So far most of my cards haven't been in that league, but I have occasionally considered selling off a bunch of the "better" ones that aren't in great condition.
Except the one time I did that I regret, and still haven't finished that set a second time.