Non-refundable initiation
The most common structure. The fee is the price of admission and you do not see it again. Treat it as a sunk cost when comparing clubs.
Equity membership
Part of your initiation buys an ownership share. When you resign, the club or the next member may buy you out, sometimes at the current value, sometimes at what you paid. The bylaws control everything, so read them.
Refundable deposits
Some clubs take a deposit that is repaid on resignation, often only when a new member takes your place. Ask how long the resale list is and whether the refund is guaranteed or contingent.
What to ask
Is any part of initiation refundable, and under what conditions? What is the current wait for a buyout? Has the club ever changed the terms retroactively?