14 degrees C is a great storing temperature and what many experts recommend. Provided the temperature remains at that point and only varies a few degrees through out the year... I would suggest "NOT" buying a cooling unit. The two biggest enemies of wine are heat and temperature change.
One more note... 14 degrees Celsius will allow you to age your wine quite a long time... Personally, I prefer 16 degrees Celsius so that I can enjoy the wine and not be forced to leave it to my children... or even my eventual grand children!