I would echo the vote for worrying about temperature more than about humidity. If you can control the temperature, then there are many ways to deal with the humidity -- everything from ignoring it and just planning to seal your cheeses after the rind is well established, to low-tech approaches using ripening boxes or a cheesecloth hanging in water, to high-tech approaches using controllers and humidifiers. But the reverse is not true - you can't control the humidity, and then just ignore the temperature, or deal with it with a low-tech approach like a ripening box.
FWIW, I only use low-tech methods in my "cave." My "cave" is a medium-sized wine cooler that uses a compressor rather than a TEC system, and it has the ability to set the target temperature as desired. I bought it used off of an internet ad. For cheeses that really, really need a high humidity (e.g., camembert), I use ripening boxes. For most of the cheeses I make, though, I have found that I can age them for two weeks to a month or so without cracking even when the humidity stays at 50%-70%. (The lower figure is what I generally have without using anything; the higher figure is the best I can get with a cheesecloth hanging in a bowl of filtered water.) After the rind is well developed, I seal them, and then they can age for the rest of the time needed. Note that with some cheeses that are intended to be very dry (e.g., parma style), I may let them age for a couple of months before sealing. The result is no doubt not exactly correct ... but it sure is good!