Money wise, the way I look at "high cost" energy saving things is over the
long term... Best to do it now rather than wait.

-The cost for making the upgrade or modification will be much higher years
from now.
-The cost of energy will be much higher years from now.
-If I do it now, I can start saving on reduced energy costs beginning this
year, so the total savings over the period of my life will be greater.
(Assuming I will live in the same house for the rest of my life.)
-Once the upgrade is paid for, I will have a lower monthly cost of living.

So if I can swing it financially, I will tend to do things *now* rather
than wait, like installing Energy Star windows, adding more insulation,
buying a more efficient A/C unit, or buying a new Energy Star appliance.

I am flat broke for a few years paying for these things, but then due to
the savings, I am able to pay for them sooner.

Also I really like it when my neighbors tell me their heating cost is $400
a month and I know my heating cost is only $50 a month!