After I fill and purge my kegs, I simply put them in the basement. As long as the temperature isn't ignorant high, then the beer should be fine. In fact, think of the keg as a secondary. My pipeline allows me to have several kegs (conditioning) for up to several months. I wouldn't go crazy and leave them there for years, but months is fine. As a general rule, the longer the conditioning time (with maybe the exception of some wheats or IPAs), the better the brew.