Collectibles for the gullible

Coins

Coin collecting is a hobby as old as, well, coins. And older coins can be valuable for a two reasons: because they are rare or because they are made of rare metals, says Andrew Mellen, a New York-based professional organizer who specializes in identifying items in your home that could be resold.

Yes, you can get really lucky if you make sure to look at the coins that come your way.

But that doesn't mean you're always going to strike it rich, whether you're buying packets of coins from the Franklin Mint, commemorative coins (which don't appreciate in value and typically only resell for the medal's meltdown value) or hoping that old coins you hold on to will appreciate in value.

That's because, Mellen says, coin and metal markets are volatile. Just look at what's happened to gold prices, which have fallen about a third from 2011 highs.

"I wouldn’t necessarily encourage people to look to coin collecting as a way of investing or trying to secure some sort of financial future," he says.