It's best to find a place in your home without drafts for the cage, because spending too much time in a draftly place can make a bird sick. As far as the temperature, 70 degrees is okay. However, if the particular bird lived in a warmer environment, it's a good idea to start with a temperature close to his/her previous home, and drop it a degree or two each day so s/he can acclimate.
If you keep your house cooler than 70, you can provide supplemental heat for the bird with heat lamps, heated perches, or a heat panel. The panels are expensive, but they work great. My bird loves his. http://www.avitec.com/Avi-Temp-Infrared-...-p/ihp.htm
