As long as your fermentation has completed, you no longer need to maintain fermentation temperatures. Just remember, there is an upper-limit as to how hot you can actually store beer for. I would never keep my beer in an area with 70F+ temps for long periods of time after fermentation. This will speed up the aging process of your batch, forcing you to drink it faster!
Like I said though, as long as fermentation is complete, move that carboy out to get another one in. Temperature control is most important during active fermentation.