I talked with a big-bank Loan officer today (a friend, over dinner).
I asked, "if a million dollar baseball card became available, can i get a loan?"
He said: Sure, but ...
(#1) The most they'd loan you is 65% of a big-ticket luxury item.
You have to have skin in the game.
(#2) They would keep possession of the card in a secured collateral vault until the last payment.
Kind of like layaway, this insures the item's safety & condition.
The good news is that the loan is 'secured' and they can offer low-interest rates.
... so, if that MUST HAVE card comes along, banks will make loans, but you better be sitting on 35% cash.