Many varying opinions about humidity levels, Steve, I prefer mine 65% or lower. 70% is the highest end of the spectrum, but I think cigars smoke too "wet" at 70%.
As far as controlling temps, I keep my house at 70* in the summer. If that is not an option for you, I would keep my humidor in a place that receives no direct sunlight. A basement is great if you have ones, temps will be naturally cooler there. If not a basement, at least in what tends to be the coolest part of your home.
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