Oh, a survivalist… In that case, you have several viable options…
1.) Your best bet is to buy land with a lake that you can build a small hydroelectric plant. Install two or three redundant A/C and other critical systems, and also keep plenty of spare parts in storage (plan like you’re going on an interstellar voyage on board a starship).
2.) or build your luxury survival shelter underground with at least 20’ of soil between the roof and the surface. Ambient temperature will be about 50F. As a SF writer, I’ve given thought to such things,myself. I envision digging a deep wide pit, install several quonset hut structures on concrete slab floors connected by cross corridors, cover the whole thing with concrete (except for the entrance tunnel). amd then bury it again and plant trees and grass above it. Disguse the entrance like a natural cave. Of the qunset hurts, one is your living quarters, one is the mechanical systems, the rest are gardens (you’ll want several independent ones to prevent disease from destroying your entire enclosed ecology). Some basic vegetables like potatoes, carrots, and tomatoes. And few varieties of fruit trees like apples, ranges and grapes. And grains like wheat, rye, and rice. You’ll need chickens for eggs and goats for milk and cheese. Your well, leach field, electrical main from your hydroelectric plant, etc, will be underground and inaccessible from the surface.
If you do go the way of A/C, your best bet is to install a water-cooled central air conditioning system. By water cooled, I mean that the condensor coil is underground or at the bottom of a nearby lake, and dumps its heat into the aquifier, rather than the atmosphere like conventional A/C systems do (this isn’t sci-fi—such systems exist where conventional above-ground A/C condensor units are impractical). Such a system is more efficient, and also secure from bands of raiding zombies in the radioactive atmosphere.