You can always think about having the coin slabbed. My preference is not to do that. That is just me.
1.
I prefer ex British
Royal Mint hard acrylic plastic screw sealed capsules.
I get them from my LCS for 50 cents each.
The seal is far more positive than simple snap shut capsules.
For very valuable coins, I even use the ex British
Royal Mint coin cases as well, and put the capsules in the felt lined case used for individual proof coins. The cases cost me a dollar each.
They were originally used for individual proof coins, or were for individually sealed coins in proof sets.
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2.
Nevertheless, snap sealed acrylic capsules are still useful. I occasionally use these as well, and if they are small enough, I put the encapsulated coin straight into a 20 pocket album page.
Sometimes, (if the capsule is small enough), I will put the capsule in a cardboard mylar 2x2 flip, before putting
that into a 20 pocket album page.
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3.
Even simpler, I will put a valuable coin in a custom made flip, made by folding a piece of clear acetate sheet, recovered from food packaging, purchased at a supermarket. The coin goes into the flip that I have made, stapled and then put inside a standard 2x2 cardboard flip (as above), which is then put into a standard 20 pocket album page.
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I have used ALL THREE methods quite successfully, and without any problems. My avatar coin (ancient Greek gold stater), is stored by the third method.