It depends on what you need. Do you carry a lot of cards? Cash? Coins? I have the flap card holder and it fits all of my cards perfectly. However, I don't carry a lot of cash on me or hold on to any coins.
Note: there's a difference between the flap card holder and the flap wallet. I personally love the look of any of the flap SLGs from Chanel the most. They also come in different sizes.
The price range for all of them vary, but I suggest the flap wallet (regular size). It has room for several cards, cash, and coins. But it's based on your preference.

Let me know what you decide! I attached examples of the flap wallet from Chanel's website.
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