First and foremost, always buy what you like, not what someone tells you is worth buying. After all, you’re the one that will likely be drinking the wine. To find out what you like, educate your palate by getting out to as many wineries or tastings as possible and also talk to other wine lovers or tasting room staff for recommendations.
If you’re planning to buy wines to age or even as investments, you’ll generally have to spend more for higher quality wines because not all wines will necessarily improve with age. Wineries will always be able to advise you about how long a wine can be aged, which can be anywhere from a couple of years for some white wines up to a decade or more for some red wines. Even after just a few years in a cellar, a good red wine can dramatically improve. Winemaster Ed Sbragia’s advice on purchasing wine is to "always buy three bottles plus a case. Drink one bottle right away. Drink the next in 6 months and drink the third bottle a year from date of purchase. Then you'll know exactly when to enjoy the case."
While all your wine is aging, however, you’ll need something to drink for those days you don’t want to necessarily open an expensive wine. This is why buying a small stock of cheaper, everyday wine is always a good idea. Then you can enjoy a bottle of wine on a whim without feeling guilty about drinking your investment before it reaches its peak.
Wine is a commodity with its own boom and bust cycles. It has not generally reaped the returns that you might expect from an ordinary investment portfolio. Having said that, some lucky collectors hit gold when the reasonably priced wines that they bought a long time ago suddenly come into great demand.
As a general rule, beware of starting a cellar simply for investment purposes. That's not to say that there will not be good returns made on your wine, but to ensure you get the best return on your wines there are a number of issues to take into consideration.
Buying aged wine from another collector or shop can be a gamble. Until you open the bottle, you have no idea whether the wine is corked or even whether it's still drinkable. By knowing its cellaring history, however, some of the guesswork involved is reduced.