Throwing away those festive holiday cards usually takes place around the same time you take your Christmas tree down. But, according to Good Housekeeping, maybe you should rethink that. Some of those old cards are going from $50 - $100 a piece. Wow.

Terry Kovel, who is the author of 'Kovels' Antiques & Collectibles Price Guide', says the market for vintage holiday items is rising. And he has a few guidelines for knowing whether you have actual treasure on your hands. Check out his points below, and if you see a box of vintage cards at a garage sale, buy them!

  • How old is the card?  The older the card, the harder it it to find. And sometimes that can be determined by the images and themes of the era.
  • What is the artistic value of the card? Is it mass produced, or was someone like Salvador Dalí or Norman Rockwell used to draw the images. Novelty cards with moving parts are also more valuable.
  • What is the condition of the card? This is a very important factor in how much the card is worth. Rips, tears, and stains all devalue the product, especially if they are really old.
  • Is the card signed by a celebrity? The British Royal family send out a lot of cards, and yes, they actually sign them! A Christmas card signed by Prince Charles and Princess Diana is worth about $2,000, according to the site Raptis Rare Books
  • Does the card represent an historic event or popular character of the era? Wartime images or popular toys can add to the value of the card, because they tell the time frame a card was made.