Hi, my name is Darrin Silverman and I have been collecting sportscards for the last 30 years from about the age of 8. I collect all 4 major sports and boxing cards.  I started collecting before their were mass ciruculated price guides.  The first Beckett monthly baseball came out in 1984 and with the first football coming in 1988 and the first basketball and hockey coming in 1989. 

Before these price guides cards were easy to collect and relatively inexpensive.  This 1984 guide lists Mickey Mantle Rookie, a 1951 Bowman for $300. Today that card books for $8000 in near mint condition and has sold for close to $100,000 in graded mint condition.

Here is my advice for buying sportscards as investments.  

Buy Rookies.  This is a player's first card by a major manufacturer like Topps or Upperdeck. They are usually listed in the price guides with an "R" next to the players name.  Rookie cards of a player are almost always the highest in demand of that player's cards and will apprecitate in value the fastest.

Buy Vintage Material. By that I mean cards dating before 1990.  Many dealers consider vintage as before 1980 but I include the 80's because the rookies of players like Jordan and Barry Bonds came from that time and cards are much harder to find in high grade because grading didn't become a trend until the 90's. The price of vintage rookie cards rarely drop in value, while the cards today have large movements up and down and are much more of a gamble.  Today people trying to find that rare limited edition signed card of Lebron James can spend over $1000 for a single pack of cards, which is fine if you pull a Lebron but a very poor investmant if you pull the 2nd pick in draft Darko Milicec.

Buy cards in grade 7 or higher from established grading companies. The main company today is mainly PSA which can be found at collectors.com.  Their graded cards bring the highest prices and are much easier to sell than ungraded material over ebay.  What one seller on ebay advertises as mint condition may only be near mint to you and the most important element in the value of a card is condition. You may also buy graded by GAI, and SGC. These are the 3 grading companys that auction houses like Mastronet, Lelands and Sothebys will accept for consignment when you chose to resell and that most dealers will buy often at prices that are at listed guide or higher.  Cards in grade 8 or higher seem to be breaking auction house records every month. A 1969 John Havlicek Rc card in grade 9 mint condition lists in the price guide for $2000. It recently sold at auction for over $12,000.  The same card in grade 7 condition can be purchased over ebay for under $200.  It is very difficult to detect the difference between a grade 8 and grade 9 yet the price difference can be 1000's of dollars.

When buying cards in ungraded condition you want to make sure that cards are well centered which means that the border usually white is even on both sides and top and bottom. Cards that are off center rarely reach a grade of or 9, mint condition. So remember when an ebay seller lists a card in mint condition, if it is off center it is most likely not in mint condition.  Also card dealers will act as if centering is not a big deal when they are selling a card but will offer you much less when buying claiming that centering is the reason. It is best to stick to well centered cards.  Next you want cards with 4 sharp corners. If the corners are not sharp the card will have a tough time reaching a grade higher than 5 or excellent. Grades lower than 6 are not considered investmant grade cards unless that card is very rare like a 1909 T206 Honus Wagner or a 1952 Topps Mickey Mantle. Cards like these will sell in any grade.

Make sure that card does not have any creases. Creases are small wrinkles which may be very hard to detect in scanned pictured. Often they can only be seen when the card is turned at a certain angle in the light. Nothing will bring down the value of a cards faster than a crease. Your card may be centered and have sharp corners but if a crease is detected it will not likely grade higher than a 3 or VG.

Because of creases it is my advice that you buy only graded cards, graded by the companies I listed above. You do not want to spend $1000 or more for an ungraded Bobby Orr rookie card you believed to be in nimnt condition only to find out when you send in to have it graded that the card had a crease and is worth less than $300.

Be carefull on buying cards that are already expensive from unproven players. By this I mean don't jump on the bandwagon spending 100's on packs trying to find the so called rare insert card of a player who has yet to play his first game or has yet to prove himself to be a star.  This is the equivalent of buying pink sheet or penny stocks trying to hit it big.  It is fine if you can buy these cards cheap, but you do not want to spend $500 trying to find that new insert autographed card of  Number 1 pick Reggie Bush when there is a chance he could turn out to be another Rickey Williams, who cards are basically worthless.

My final advice is to join PSA if you intend to buy sportscards as an investmant.  They are at collectors.com. For $99 you will get 6 free card gradings and a 12 month subscription to their magazine called the SMR. This will list the prices of all of the cards of the 4 major sports as well as boxing and golf cards.  You will be able to find out which year is a players rookie as well as the price of that card ranging from grade 5 to 10 which is Gem Mint. You will see that a card like a 1987 Fleer Barry Bonds Rc card books for $35 in grade 8 and $420 in grade $10. Quite a difference and in many cases your eye could not tell the difference between an 8 and a grade 10. Graded cards are usually put under 10x magnafying scopes. This is one more reason why you should stick to graded cards.

My final advise is to have fun and if you are going to buy ungraded cards do not overpay for them. Treat them as a grade 7 and do not pay mint prices for ungraded material.  It is very exciting to send in that Bonds Rc you bought over ebay ungraded for $20, and have it come back to you a grade 10, knowing that your $20 investmant is now worth over $400, not a bad return.